Texas Instruments | TPS23881 Type-4 4-Pair 8-Channel PoE PSE Controller with SRAM and 200 mΩ RSENSE (Rev. C) | Datasheet | Texas Instruments TPS23881 Type-4 4-Pair 8-Channel PoE PSE Controller with SRAM and 200 mΩ RSENSE (Rev. C) Datasheet

Texas Instruments TPS23881 Type-4 4-Pair 8-Channel PoE PSE Controller with SRAM and 200 mΩ RSENSE (Rev. C) Datasheet
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TPS23881
SLVSF02C – MARCH 2019 – REVISED OCTOBER 2019
TPS23881 Type-4 4-Pair 8-Channel PoE PSE Controller with SRAM and 200 mΩ RSENSE
1 Features
3 Description
•
The TPS23881 is an 8-channel power sourcing
equipment (PSE) controller engineered to insert
power onto Ethernet cables in accordance with the
IEEE 802.3bt standard. The eight individual power
channels can be configured in any combination of 2Pair (1-channel) or 4-Pair (2-channels) PoE Ports.
The PSE controller can detect powered devices
(PDs) that have a valid signature, determine the
power requirements of the devices according to their
classification, and apply power.
1
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
IEEE 802.3bt PSE solution for Type 3 or Type 4
Power Over Ethernet applications
Eight independent PSE channels
Resistor selectable Autonomous operation
– No external MCU required
Compatible with TI's FirmPSE system firmware
SRAM Programmable memory
Programmable power limiting accuracy ±2.5%
200-mΩ Current sense resistor
Legacy PD capacitance measurement
Selectable 2-pair or 4-pair port power allocations
– 15.4 W, 30 W, 45 W, 60 W, 75 W or 90 W
Single and dual signature PD compatibility
Dedicated 14-bit integrating current ADC per port
– Noise immune MPS for DC disconnect
– 2% Current sensing accuracy
1- or 3-Bit fast port shutdown input
Auto-class discovery and power measurement
Inrush and operational foldback protection
Flexible processor controlled operating modes
– Auto, semi auto and manual / diagnostic
Per Port voltage monitoring and telemetry
–40°C to +125°C Temperature operation
Ultra Low Alpha (ULA) packaging (TPS23881A)
The TPS23881 improves on the TPS23880 with
reduced current sense resistors, more accurate
programmable
power
limiting,
capacitance
measurement and the ability to operate from ROM
(see Device Comparison Table). The TPS23881 is
also compatible with TI's FirmPSE system firmware,
which provides a fully configurable solution for
controlling multiple TPS23881 devices in systems
offering up to 48-ports of 4-pair PoE power.
Dedicated per port ADCs provide continuous port
current monitoring and the ability to perform parallel
classification measurements for faster port turn on
times. A ±2.5% accurate programmable port power
limit provides the ability to expand the maximum
power sourced from 90 W to upwards of 125 W. The
200-mΩ current sense resistor and external FET
architecture allow designs to balance size, efficiency,
thermal and solution cost requirements.
Device Information(1)
PART NUMBER
2 Applications
•
•
•
TPS23881
Video recorder (NVR, DVR, and so forth)
Small business switch
Campus and branch switches
PACKAGE
VQFN (56)
BODY SIZE (NOM)
8.00 mm × 8.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Simplified Schematic
Note: Only four channels shown
+54V
+3.3V
2P Port #1
0.1uF
100V
VPWR
VDD
4P Port #1
DRAIN3
0.1uF
100V
Alt A
RJ45 & XFrmr
0.1uF
100V
Alt A
RJ45 & XFrmr
DRAIN1
Alt A
RJ45 & XFrmr
Alt B
0.1uF
100V
GAT3
GAT1
SEN3
SEN1
0.200:
2P Port #2
0.200:
TPS23881
KSENSEB
KSENSEA
0.200:
0.200:
SEN2
SEN4
2P Port #3
Alt A
Alt B
SDAI
SCL
4P Port #2
RJ45 & XFrmr
INT
GAT2
DRAIN2
SDAO
GAT4
DRAIN4
AUTO
Alt A
RJ45 & XFrmr
Alt A
RJ45 & XFrmr
GND
2P Port #4
10nF
I2C Bus
RAUTO
Optional
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
TPS23881
SLVSF02C – MARCH 2019 – REVISED OCTOBER 2019
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Table of Contents
1
2
3
4
5
6
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Device Comparison Table.....................................
Pin Configuration and Functions .........................
1
1
1
2
3
4
6.1 Detailed Pin Description............................................ 5
7
Specifications......................................................... 7
7.1
7.2
7.3
7.4
7.5
7.6
Absolute Maximum Ratings ...................................... 7
ESD Ratings.............................................................. 7
Recommended Operating Conditions....................... 7
Thermal Information .................................................. 7
Electrical Characteristics........................................... 8
Typical Characteristics ............................................ 14
8
Parameter Measurement Information ................ 19
9
Detailed Description ............................................ 23
8.1 Timing Diagrams ..................................................... 19
9.1
9.2
9.3
9.4
Overview .................................................................
Functional Block Diagram .......................................
Feature Description.................................................
Device Functional Modes........................................
23
27
28
30
9.5 I2C Programming ................................................... 32
9.6 Register Maps ......................................................... 35
10 Application and Implementation...................... 112
10.1 Application Information........................................ 112
10.2 Typical Application ............................................. 114
11 Power Supply Recommendations ................... 123
11.1 VDD..................................................................... 123
11.2 VPWR ................................................................. 123
12 Layout................................................................. 124
12.1 Layout Guidelines ............................................... 124
12.2 Layout Example .................................................. 125
13 Device and Documentation Support ............... 126
13.1 Documentation Support .....................................
13.2 Receiving Notification of Documentation
Updates..................................................................
13.3 Support Resources .............................................
13.4 Trademarks .........................................................
13.5 Electrostatic Discharge Caution ..........................
13.6 Glossary ..............................................................
126
126
126
126
126
126
14 Mechanical, Packaging, and Orderable
Information ......................................................... 126
4 Revision History
Changes from Revision B (August 2019) to Revision C
•
Added TPS23882 to the Device Comparison Table............................................................................................................... 3
Changes from Revision A (May 2019) to Revision B
•
Page
First public release of the Advance Information data sheet .................................................................................................. 1
Changes from Revision C (July 2019) to Revision D
2
Page
Changed from Advance Information to Production Data ....................................................................................................... 1
Changes from Original (March 2019) to Revision A
•
Page
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5 Device Comparison Table
KEY FEATURES
TPS23880
TPS23881
TPS23882
Compatible with TI's FirmPSE system
firmware
N/A
Yes
Yes
Pin to Pin compatible
Yes
Yes
Yes
8
8
8
802.3bt Type 3 or 4 (2 or 4
Pair)
802.3bt Type 3 or 4 (2 or 4
Pair)
802.3bt Type 3 (2-Pair)
0.255 Ω
0.200 Ω
0.200 Ω
N/A
Yes
2-Pair: 15.5 W or 30W
4-Pair: 30 W up to 90W
Yes
2-Pair: 15.5 W or 30 W
2-Pair PCUT programable ranges
0.5 W to 54 W
2 W to 65 W
2 W to 65 W
4-Pair PCUT programable ranges
0.5 W to 108 W
4 W to 127 W
N/A
±3.0 %
±2.5 %
N/A
N/A
1 µF to 12 µF
1 µF to 12 µF
No
Yes (TPS23881A)
N/A
16 kB
16 kB
16 kB
Number of PSE Channels
Supported IEEE 802.3 PSE Types
RSENSE
Autonomous operation
Resistor Selectable
90+ W 4-pair PCUT accuracy
Channel capacitance measurement
range
ULA Packaging
I2C Programmable SRAM Memory
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6 Pin Configuration and Functions
DGND
INT
RESET
VDD
TEST5
SCL
AUTO
A4
A3
A2
A1
SDAI
56
55
54
53
52
51
50
49
48
47
46
45
44
43
OSS
SDAO
RTQ Package With Exposed Thermal Pad
56-Pin VQFN
Top View
4
26
27
28
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GAT8
SEN8
DRAIN8
KSENSD
DRAIN7
SEN7
GAT7
GAT6
SEN6
DRAIN6
KSENSC
DRAIN5
SEN5
GAT5
NC
NC
TEST0
NC
NC
VPWR
15
16
17
NC 18
NC 19
TEST4 20
AGND 21
DRAIN4
SEN4
GAT4
Thermal Pad
TEST1
TEST2
TEST3
SEN3
DRAIN3
KSENSB
42
41
40
39
38
37
36
35
34
33
32
31
30
29
22
23
24
25
SEN1
DRAIN1
KSENSA
DRAIN2
SEN2
GAT2
GAT3
1
2
3
4
5
6
7
8
9
10
11
12
13
14
NC
GAT1
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Pin Functions
PIN
NAME
A1-4
AGND
DGND
NO.
I/O
DESCRIPTION
I2C A1-A4 address lines. These pins are internally pulled up to VDD.
48–51
I
21
—
Analog ground. Connect to GND plane and exposed thermal pad.
Digital ground. Connect to GND plane and exposed thermal pad.
46
—
DRAIN1-8
3, 5, 10, 12, 31,
33, 38, 40
I
Channel 1-8 output voltage monitor.
GAT1-8
1, 7, 8, 14, 29,
35, 36, 42
O
Channel 1-8 gate drive output.
INT
45
O
Interrupt output. This pin asserts low when a bit in the interrupt register is asserted. This output is open-drain.
KSENSA/B
4, 11
I
Kelvin point connection for SEN1-4
KSENSC/D
32, 39
I
Kelvin point connection for SEN5-8
15, 16, 18, 19
O
No connect pins. These pins are internally biased at 1/3 and 2/3 of VPWR in order to control the voltage
gradient from VPWR. Leave open.
No connect pin. Leave open.
NC
22, 27, 28, 52
—
OSS
56
I
Channel 1-8 fast shutdown. This pin is internally pulled down to DGND.
RESET
44
I
Reset input. When asserted low, the TPS23881 is reset. This pin is internally pulled up to VDD.
SCL
53
I
Serial clock input for I2C bus.
SDAI
54
I
Serial data input for I2C bus. This pin can be connected to SDAO for non-isolated systems.
SDAO
55
O
Serial data output for I2C bus. This pin can be connected to SDAI for non-isolated systems. This output is opendrain.
Autonomous mode enable and selection pin.
AUTO
52
I/O
SEN1-8
2, 6, 9, 13, 30,
34, 37, 41
I
TEST0-5
20, 23, 24, 25,
26, 47
I/O
Used internally for test purposes only. Leave open.
Thermal pad
—
—
The DGND and AGND terminals must be connected to the exposed thermal pad for proper operation.
VDD
43
—
Digital supply. Bypass with 0.1 µF to DGND pin.
VPWR
17
—
Analog 54-V positive supply. Bypass with 0.1 µF to AGND pin.
Channel 1-8 current sense input.
6.1 Detailed Pin Description
The following descriptions refer to the pinout and the functional block diagram.
DRAIN1-DRAIN8: Channels 1-8 output voltage monitor and detect sense. Used to measure the port output
voltage, for port voltage monitoring, port power good detection and foldback action. Detection probe currents also
flow into this pin.
The TPS23881 uses an innovative 4-point technique to provide reliable PD detection and avoids powering an
invalid load. The discovery is performed by sinking two different current levels via the DRAINn pin, while the PD
voltage is measured from VPWR to DRAINn. If prior to starting a new detection cycle the port voltage is >2.5 V,
an internal 100-kΩ resistor is connected in parallel with the port and a 400-ms detect backoff period is applied to
allow the port capacitor to be discharged before the detection cycle starts.
There is an internal resistor between each DRAINn pin and VPWR in any operating mode except during
detection or while the port is ON. If the port n is not used, DRAINn can be left floating or tied to GND.
GAT1-GAT8: Channels 1-8 gate drive outputs are used for external N-channel MOSFET gate control. At port
turn on, it is driven positive by a low current source to turn the MOSFET on. GATn is pulled low whenever any of
the input supplies are low or if an overcurrent timeout has occurred. GATn is also pulled low if the port is turned
off by use of manual shutdown inputs. Leave floating if unused.
For improved design robustness, the current foldback functions limit the power dissipation of the MOSFET during
low resistance load or short-circuit events and during the inrush period at port turn on. There is also fast overload
protection comparator for major faults like a direct short that forces the MOSFET to turn off in less than a
microsecond.
The circuit leakage paths between the GATn pin and any nearby DRAINn pin, GND or Kelvin point connection
must be minimized (< 250 nA), to ensure correct MOSFET control.
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Detailed Pin Description (continued)
INT: This interrupt output pin asserts low when a bit in the interrupt register is asserted. This output is opendrain.
KSENSA, KSENSB, KSENSC, KSENSD: Kelvin point connection used to perform a differential voltage
measurement across the associated current sense resistors.
Each KSENS is shared between two neighbor SEN pins as following: KSENSA with SEN1 and SEN2, KSENSB
with SEN3 and SEN4, KSENSC with SEN5 and SEN6, KSENSD with SEN7 and SEN8. To optimize the
measurement accuracy, ensure proper PCB layout practices are followed.
OSS: Fast shutdown, active high. This pin is internally pulled down to DGND, with an internal 1-µs to 5-µs
deglitch filter.
The turn off procedure is similar to a port reset using Reset command (1Ah register). The 3-bit OSS function
allows for a series of pulses on the OSS pin to turn off individual or multiple ports with up to 8 levels of priority.
RESET: Reset input, active low. When asserted, the TPS23881 resets, turning off all ports and forcing the
registers to their power-up state. This pin is internally pulled up to VDD, with internal 1-µs to 5-µs deglitch filter.
The designer can use an external RC network to delay the turn-on. There is also an internal power-on-reset
which is independent of the RESET input.
SCL: Serial clock input for I2C bus.
SDAI: Serial data input for I2C bus. This pin can be connected to SDAO for non-isolated systems.
SDAO: Open-drain I2C bus output data line. Requires an external resistive pull-up. The TPS23881 uses separate
SDAO and SDAI lines to allow optoisolated I2C interface. SDAO can be connected to SDAI for non-isolated
systems.
AUTO: Autonomous mode selection pin: Floating this pin will disable autonomous operation. Tying this pin to
GND through a resistor (RAUTO) will enable autonomous operation at selectable port power allocation levels. A 10
nF capacitor is required between the Auto pin and GND if RAUTO is connected.
A4-A1: I2C bus address inputs. These pins are internally pulled up to VDD. See PIN STATUS Register for more
details.
SEN1-8: Channel current sense input relative to KSENSn (see KSENSn description). A differential measurement
is performed using KSENSA-D Kelvin point connection. Monitors the external MOSFET current by use of a
0.200-Ω current sense resistor connected to GND. Used by current foldback engine and also during
classification. Can be used to perform load current monitoring via ADC conversion.
When the TPS23881 performs the classification measurements, the current flows through the external
MOSFETs. This avoids heat concentration in the device and makes it possible for the TPS23881 to perform
classification measurements on multiple ports at the same time. For the current limit with foldback function, there
is an internal 2-µS analog filter on the SEN1-8 pins to provide glitch filtering. For measurements through an ADC,
an anti-aliasing filter is present on the SEN1-8 pins. This includes the port-powered current monitoring, port
policing, and DC disconnect.
If the port is not used, tie SENn to GND.
VDD: 3.3-V logic power supply input.
VPWR: High voltage power supply input. Nominally 54 V.
AGND and DGND: Ground references for internal analog and digital circuitry respectively. Not connected
together internally. Both pins require a low resistance path to the system GND plane. If a robust GND plane is
used to extract heat from the device's thermal pad, these pins may be connected together through the thermal
pad connection on the pcb.
6
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7 Specifications
7.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
Voltage
Sink Current
MIN
MAX
VPWR
–0.3
70
V
VDD
–0.3
4
V
OSS, RESET, A1-A4, AUTO, SDAI, SDAO, SCL, INT
–0.3
4
V
SEN1-8, KSENSA, KSENSB, KSENSC, KSENSD
–0.3
3
V
GATE1-8
–0.3
12
V
DRAIN1-8
–0.3
70
V
TEST0-3, ATST_DCPL0, DTST_DCPL1
–0.3
4
V
AGND - DGND
–0.3
0.3
V
20
mA
260
°C
150
°C
INT, SDA
Lead Temperature 1/6mm from case for 10 seconds
Tstg
(1)
Storage temperature
–65
UNIT
Stresses beyond those listed underAbsolute Maximum Rating may cause permanent damage to thedevice. These are stress ratings
only, which do not imply functional operation of the device atthese or any other conditions beyond those indicated under
RecommendedOperating Condition. Exposure to absolute-maximum-rated conditions for extended periodsmay affect device reliability.
7.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
Electrostatic discharge
Human body model (HBM), per
ANSI/ESDA/JEDEC JS-001, allpins (1)
±2000
Charged device model (CDM), per JEDEC
specificationJESD22-C101, all pins (2)
± 500
UNIT
V
JEDEC documentJEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC documentJEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
7.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
VVDD
VVPWR
MIN
NOM
MAX
3
3.3
3.6
44
54
57
V
1
V/µs
400
kHz
125
°C
Voltage Slew rate on VPWR
fSCL
I2C Clock Frequency
TJ
Junction temperature
–40
UNIT
V
7.4 Thermal Information
TPS23881
THERMAL METRIC (1)
RTQ Package (VQFN)
UNIT
56 PINS
RθJA
Junction-to-ambient thermal resistance
25.3
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
9.7
°C/W
RθJB
Junction-to-board thermal resistance
3.7
°C/W
ΨJT
Junction-to-top characterization parameter
0.2
°C/W
ΨJB
Junction-to-board characterization parameter
3.7
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
0.5
°C/W
(1)
For more information abouttraditional and new thermal metrics, see theSemiconductor and IC Package ThermalMetrics application
report.
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7.5 Electrical Characteristics
Conditions are –40 < TJ < 125 °C unless otherwisenoted.VVDD = 3.3 V,VVPWR = 54 V, VDGND = VAGND,DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn =0. Positive currents are into
pins. RSENSE = 0.200 Ω, to KSENSA (SEN1 orSEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to
KSENSD (SEN7 or SEN8). Typicalvalues are at 25 °C. All voltages are with respect to AGND unless otherwise noted.
Operatingregisters loaded with default values unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
10
INPUT SUPPLY VPWR
IVPWR
VPWR Current consumption
VVPWR = 54 V
VUVLOPW_F
VPWR UVLO falling threshold
Check internal oscillator stops operating
VUVLOPW_R
VPWR UVLO rising threshold
VPUV_F
VPWR Undervoltage falling threshold
VPUV threshold
12.5
mA
14.5
17.5
V
15.5
18.5
V
26.5
28
V
6
12
mA
25
INPUT SUPPLY VDD
IVDD
VDD Current consumption
VUVDD_F
VDD UVLO falling threshold
VUVDD_R
VDD UVLO rising threshold
VUVDD_HYS
Hysteresis VDD UVLO
VUVW_F
VDD UVLO warning threshold
For channel deassertion
2.1
2.25
2.4
V
2.45
2.6
2.75
V
0.35
VDD falling
2.6
V
2.8
3
V
A/D CONVERTERS
TCONV_I
Conversion time
All ranges, each channel
0.64
0.8
0.96
ms
TCONV_V
Conversiontime
All ranges, each channel
0.82
1.03
1.2
ms
TINT_CUR
Integration time, Current
Each channel, channel ON current
TINT_DET
Integration time, Detection
TINT_channelV
Integration time, Channel Voltage
TINT_inV
Integration time, Input Voltage
channel powered
VVPWR = 57 V
Input voltage conversion scale factor and
accuracy
VVPWR = 44 V
VVPWR - VDRAINn = 57 V
Powered Channel voltage conversion
scale factor and accuracy
VVPWR - VDRAINn = 44 V
δV/VChannel
Voltage reading accuracy
Channel current = 770 mA
Channel Current = 100 mA
Current reading accuracy
122
ms
20
ms
3.25
4.12
4.9
ms
3.25
4.12
4.9
15175
15565
15955
Counts
55.57
57
58.43
V
11713
12015
12316
Counts
42.89
44
45.10
V
15175
15565
15955
Counts
55.57
57
58.43
V
11713
12015
12316
Counts
42.89
44
45.10
V
2.5
%
8431
8604
8776
770
785.4
mA
1084
1118
1152
Counts
97
100
103
mA
–3
3
Channel Current =770 mA
–2
2
Channel currents = 1.5 A, 2xFBn = 1
σI
Current Reading Repeatability
Full Scale reading
δR/RChannel
Resistance reading accuracy
15 kΩ ≤ RChannel ≤ 33 kΩ, CChannel ≤ 0.25
µF
Ibias
Sense Pin bias current
Channel ON or during class
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ms
754.5
Channel Current =100 mA
Powered Channel current ful scale
output
8
102
16.6
–2.5
Powered Channel current conversion
scale factor and accuracy
δI/IChannel
82
13.1
14959
15671
1.34
1.400
Counts
%
Counts
A
–7.5
7.5
mA
–7
7
%
–2.5
0
µA
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Electrical Characteristics (continued)
Conditions are –40 < TJ < 125 °C unless otherwisenoted.VVDD = 3.3 V,VVPWR = 54 V, VDGND = VAGND,DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn =0. Positive currents are into
pins. RSENSE = 0.200 Ω, to KSENSA (SEN1 orSEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to
KSENSD (SEN7 or SEN8). Typicalvalues are at 25 °C. All voltages are with respect to AGND unless otherwise noted.
Operatingregisters loaded with default values unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
12.5
V
GATE 1-8
VGOH
Gate drive voltage
VGATEn , IGATE = -1 µA
10
IGO-
Gate sinking current with Power-on
Reset, OSS detected or channel turnoff
command
VGATEn = 5 V
60
100
190
mA
IGO short-
Gate sinking current with channel shortcircuit
VGATEn = 5 V,
VSENn ≥ Vshort (or Vshort2X if 2X mode)
60
100
190
mA
IGO+
Gate sourcing current
VGATEn = 0 V, default selection
39
50
63
µA
tD_off_OSS
Gate turnoff time from 1-bit OSS input
From OSS to VGATEn < 1 V,
VSENn = 0 V, MbitPrty = 0
1
5
µs
tOSS_OFF
Gate turnoff time from 3-bit OSS input
From Start bit falling edge to VGATEn <
1 V,
VSENn = 0 V, MbitPrty = 1
72
104
µs
tP_off_CMD
Gate turnoff time from channel turnoff
command
From Channel off command (POFFn =
1) to VGATEn < 1 V, VSENn = 0 V
300
µs
tP_off_RST
Gate turnoff time with /RESET
From /RESET low to VGATEn < 1 V,
VSENn = 0 V
1
5
µs
VPGT
Power-Good threshold
Measured at VDRAINn
1
2.13
3
V
VSHT
Shorted FET threshold
Measured at VDRAINn
4
6
8
V
Resistance from DRAINn to VPWR
Any operating mode except during
detection or while the Channel is ON,
including in device RESET state
80
100
190
kΩ
Start of Autoclass Detection
Measured from the start of Class
90
100
ms
Measured from the end of Inrush
1.4
1.6
s
10
ms
1.9
s
0.3
s
Counts
DRAIN 1-8
RDRAIN
AUTOCLASS
tClass_ACS
tAUTO_PSE1
Start of Autoclass Power Measurement
tAUTO
Duration of Autoclass Power
Measurement
tAUTO_window
Autoclass Power Measurement Sliding
Window
PAC
Autoclass Channel Power conversion
scale factor and accuracy
Measured from setting the MACx bit
while channel is already powered
1.7
1.8
0.15
VPWR = 52 V, VDRAINn = 0 V,
Channel current = 770 mA
76
80
84
VPWR = 50 V, VDRAINn = 0 V,
Channel current = 100 mA
9
10
11
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Electrical Characteristics (continued)
Conditions are –40 < TJ < 125 °C unless otherwisenoted.VVDD = 3.3 V,VVPWR = 54 V, VDGND = VAGND,DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn =0. Positive currents are into
pins. RSENSE = 0.200 Ω, to KSENSA (SEN1 orSEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to
KSENSD (SEN7 or SEN8). Typicalvalues are at 25 °C. All voltages are with respect to AGND unless otherwise noted.
Operatingregisters loaded with default values unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
First and 3rd detection points
VVPWR - VDRAINn = 0 V
145
160
190
2nd and 4th detection points VVPWR VDRAINn = 0 V
235
270
300
98
110
118
23.5
26
29
V
15
kΩ
100
kΩ
26.5
kΩ
DETECTION
IDISC
Detection current
µA
ΔIDISC
2nd – 1st detection currents
VVPWR - VDRAINn = 0 V
Vdet_open
Open circuit detection voltage
Measured as VVPWR - VDRAINn
RREJ_LOW
Rejected resistance low range
RREJ_HI
Rejected resistance high range
33
RACCEPT
Accepted resistance range
19
RSHORT
Shorted Channel threshold
ROPEN
Open Channel Threshold
tDET
Detection Duration
Time to complete a detection, 4Pxx = 0
tCC
Connection Check Duration
Time to complete connection check after
a valid detection, 4Pxx = 1
tDET_BOFF
Detect backoff pause between discovery
attempts
tDET_DLY
0.86
25
360
400
275
VVPWR - VDRAINn > 2.5 V
300
VVPWR - VDRAINn < 2.5 V
20
Detection delay
From command or PD attachment to
Channel detection complete 4Pxx = 0
Capactance Measurement
Cport = 10uF
µA
Ω
kΩ
350
425
ms
150
400
ms
400
500
ms
100
ms
590
ms
8.5
10
11.5
uF
15.5
18.5
20.5
V
65
75
CLASSIFICATION
VCLASS
Classification Voltage
VVPWR - VDRAINn, VSENn ≥ 0 mV
Ichannel ≥ 180 µA
ICLASS_Lim
Classification Current Limit
VVPWR - VDRAINn = 0 V
ICLASS_TH
Classification Threshold Current
90
mA
Class 0-1
5
8
mA
Class 1-2
13
16
mA
Class 2-3
21
25
mA
Class 3-4
31
35
mA
Class 4-Class overcurrent
45
51
mA
tLCE
Classification Duration (1st Finger)
From detection complete
95
105
ms
tCLE2-5
Classification Duration (2nd- 5th Finger)
From Mark complete
6.5
12
ms
VMARK
Mark Voltage
4 mA ≥ IChannel ≥ 180 µA
VVPWR - VDRAINn
7
10
V
IMARK_Lim
Mark Sinking Current Limit
VVPWR - VDRAINn = 0 V
60
90
mA
tME
Mark Duration
12
ms
MARK
10
6
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Electrical Characteristics (continued)
Conditions are –40 < TJ < 125 °C unless otherwisenoted.VVDD = 3.3 V,VVPWR = 54 V, VDGND = VAGND,DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn =0. Positive currents are into
pins. RSENSE = 0.200 Ω, to KSENSA (SEN1 orSEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to
KSENSD (SEN7 or SEN8). Typicalvalues are at 25 °C. All voltages are with respect to AGND unless otherwise noted.
Operatingregisters loaded with default values unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
DCDTxx = 0
0.8
1.3
1.8
mV
DCDTxx = 1
0.4
0.9
1.4
mV
TMPDO = 00
320
400
ms
TMPDO = 01
75
100
ms
TMPDO = 10
150
200
ms
TMPDO = 11
600
800
ms
2.5
3
ms
DC DISCONNECT
VIMIN
DC disconnect threshold
tMPDO
PD Maintain Power signature dropout
time limit
tMPS
PD Maintain Power Signature time for
validity
PORT POWER POLICING
δPCUT/PCUT
PCUT tolerance
POL ≤ 15W
0
5
10
%
δPCUT/PCUT
PCUT tolerance
15W < POL < 90W
0
3
6
%
δPCUT/PCUT
PCUT tolerance
POL ≥ 90W
0
2.5
5
%
TOVLD = 00
50
tOVLD
PCUT time limit
70
TOVLD = 01
25
35
TOVLD = 10
100
140
TOVLD = 11
200
280
ms
PORT CURRENT INRUSH
IInrush limit, ALTIRNn = 0
VInrush
IInrush limit, ALTIRNn = 1
tSTART
Maximum current limit duration in startup
VVPWR - VDRAINn = 1 V
19
30
41
VVPWR - VDRAINn = 10 V
19
30
41
VVPWR - VDRAINn = 15 V
33
44
55
VVPWR - VDRAINn = 30 V
80
VVPWR - VDRAINn = 55 V
80
VVPWR - VDRAINn = 1 V
19
30
41
VVPWR - VDRAINn = 10 V
36
47
58
VVPWR - VDRAINn = 15 V
53
64
75
VVPWR - VDRAINn = 30 V
80
90
VVPWR - VDRAINn = 55 V
80
90
TSTART = 00
50
70
TSTART = 01
25
35
TSTART = 10
100
140
90
90
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Electrical Characteristics (continued)
Conditions are –40 < TJ < 125 °C unless otherwisenoted.VVDD = 3.3 V,VVPWR = 54 V, VDGND = VAGND,DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn =0. Positive currents are into
pins. RSENSE = 0.200 Ω, to KSENSA (SEN1 orSEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to
KSENSD (SEN7 or SEN8). Typicalvalues are at 25 °C. All voltages are with respect to AGND unless otherwise noted.
Operatingregisters loaded with default values unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
PORT CURRENT FOLDBACK
ILIM 1X limit, 2xFB = 0 and ALTFBn = 0
VLIM
ILIM 1X limit, 2xFB = 0 and ALTFBn = 1
ILIM 2X limit, 2xFB = 1 and ALTFBn = 0
VLIM2X
ILIM 2X limit, 2xFB = 1 and ALTFBn = 1
ILIM time limit
tLIM
2xFBn = 1
VDRAINn = 1 V
80
90
VDRAINn = 15 V
80
90
VDRAINn = 30 V
51
58
65
VDRAINn = 50 V
23
30
37
VDRAINn = 1 V
80
90
VDRAINn = 25 V
80
90
VDRAINn = 40 V
45
51
VDRAINn = 50 V
23
30
37
VDRAINn = 1 V
245
250
262
VDRAINn = 10 V
164
180
196
VDRAINn = 30 V
51
58
64
VDRAINn = 50 V
23
30
37
VDRAINn = 1 V
245
250
262
VDRAINn = 20 V
139
147
155
VDRAINn = 40 V
45
51
57
VDRAINn = 50 V
23
30
37
2xFBn = 0
55
60
65
TLIM = 00
55
60
65
TLIM = 01
15
16
17
TLIM = 10
10
11
12
TLIM = 11
6
6.5
7
mV
57
mV
ms
SHORT CIRCUIT DETECTION
Vshort
ISHORT threshold in 1X mode and during
inrush
205
245
Vshort2X
ISHORT threshold in 2X mode
280
320
tD_off_SEN
Gate turnoff time from SENn input
2xFBn = 0, VDRAINn = 1 V
From VSENn pulsed to 0.425 V.
0.9
2xFBn = 1, VDRAINn = 1 V
From VSENn pulsed to 0.62 V.
0.9
mV
µs
CURRENT FAULT RECOVERY (BACKOFF) TIMING
ted
Error delay timing. Delay before next
attempt to power a channel following
power removal due to error condition
δIfault
Duty cycle of Ichannel with current fault
PCUT , ILIM or IInrush fault Semi-auto mode
0.8
1
5.5
1.2
s
6.7
%
THERMAL SHUTDOWN
Shutdown temperature
Temperature rising
Hysteresis
12
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146
°C
7
°C
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SLVSF02C – MARCH 2019 – REVISED OCTOBER 2019
Electrical Characteristics (continued)
Conditions are –40 < TJ < 125 °C unless otherwisenoted.VVDD = 3.3 V,VVPWR = 54 V, VDGND = VAGND,DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn =0. Positive currents are into
pins. RSENSE = 0.200 Ω, to KSENSA (SEN1 orSEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to
KSENSD (SEN7 or SEN8). Typicalvalues are at 25 °C. All voltages are with respect to AGND unless otherwise noted.
Operatingregisters loaded with default values unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
DIGITAL I/O (SCL, SDAI, A1-A4, /RESET, OSS unless otherwise stated)
VIH
Digital input High
VIL
Digital input Low
VIT_HYS
Input voltage hysteresis
2.1
V
0.9
0.17
V
V
Digital output Low
SDAO at 9mA
0.4
Digital output Low
/INT at 3mA
0.4
V
Rpullup
Pullup resistor to VDD
/RESET, A1-A4, TEST0
30
50
80
kΩ
Rpulldown
Pulldown resistor to DGND
OSS, TEST1, TEST2
30
50
80
kΩ
tFLT_INT
Fault to /INT assertion
Time to internally register an Interrupt
fault, from Channel turn off
50
500
µs
TRESETmin
/RESET input minimum pulse width
5
µs
Tbit_OSS
3-bit OSS bit period
MbitPrty = 1
24
25
26
µs
tOSS_IDL
Idle time between consecutive shutdown
code transmission in 3-bit mode
MbitPrty = 1
48
50
tr_OSS
Input rise time of OSS in 3-bit mode
0.8 V → 2.3 V, MbitPrty = 1
1
300
ns
tf_OSS
Input fall time of OSS in 3-bit mode
2.3 V → 0.8 V, MbitPrty = 1
1
300
ns
20
ms
400
kHz
VOL
V
µs
I2C TIMING REQUIREMENTS
tPOR
Device power-on reset delay
fSCL
SCL clock frequency
10
tLOW
LOW period of the clock
0.5
µs
tHIGH
HIGH period of the clock
0.26
µs
tfo
SDAO output fall time
SDAO, 2.3 V → 0.8 V, Cb = 10 pF, 10
kΩ pull-up to 3.3 V
10
50
ns
SDAO, 2.3 V → 0.8 V, Cb = 400 pF, 1.3
kΩ pull-up to 3.3 V
10
50
ns
10
pF
6
pF
CI2C
SCL capacitance
CI2C_SDA
SDAI, SDAO capacitance
tSU,DATW
Data setup tme (Write operation)
50
tHD,DATW
Data hold time (Write operation)
0
tHD,DATR
Data hold time (Read operation)
150
400
ns
tfSDA
Input fall times of SDAI
2.3 V → 0.8 V
20
120
ns
trSDA
Input rise times of SDAI
0.8 V → 2.3 V
20
120
ns
tr
Input rise time of SCL
0.8 V → 2.3 V
20
120
ns
tf
Input fall time of SCL
2.3 V → 0.8 V
20
120
ns
tBUF
Bus free time between a STOP and
START condition
0.5
µs
tHD,STA
Hold time After (Repeated) START
condition
0.26
µs
tSU,STA
Repeated START condition setup time
0.26
µs
tSU,STO
STOP condition setup time
0.26
µs
tDG
Suppressed spike pulse width, SDAI and
SCL
50
ns
tWDT_I2C
I2C Watchdog trip delay
1.1
ns
ns
2.2
3.3
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7.6 Typical Characteristics
9.8
9.6
9.4
9.2
9
8.8
8.6
8.4
8.2
8
7.8
7.6
7.4
7.2
7
6.8
-40
19
18
17.5
17
16.5
16
15.5
15
14.5
-20
0
20
40
60
80
Temperature (qC)
100
120
14
-40
140
28.8
5.5
28.2
5.25
27.6
5
IVDD (mA)
VVPWR (V)
40
60
80
Temperature (qC)
100
120
140
D002
5.75
27
26.4
4.75
4.5
25.8
4.25
25.2
4
24.6
3.75
-20
0
20
40
60
80
Temperature (qC)
100
120
3.5
-40
140
2.7
ISENSE ( PA)
2.6
2.5
2.4
2.3
2.2
2.1
-20
0
20
40
60
80
Temperature (qC)
0
20
100
120
140
0.2
0.1
0
-0.1
-0.2
-0.3
-0.4
-0.5
-0.6
-0.7
-0.8
-0.9
-1
-1.1
-1.2
-40
100
120
140
D004
Classification
Port On
Port Off
-20
D005
Figure 5. VDUV Thresholds vs Temperature
40
60
80
Temperature (qC)
Figure 4. VDD Current Consumption vs Temperature
VDUV_Falling
VDUV_Rising
2.8
-20
D003
2.9
VVDD (V)
20
6
VPUV_Falling
VPUV_Rising
Figure 3. VPUV Thresholds vs Temperature
14
0
Figure 2. VPWR UVLO Thresholds vs Temperature
30
29.4
2
-40
-20
D001
Figure 1. VPWR Current Consumption vs Temperature
24
-40
VUVLO_Falling
VUVLO_Rising
18.5
VVPWR (V)
IVPWR (mA)
Conditions are –40 < TJ < 125 °C unless otherwise noted.VVDD = 3.3 V, VVPWR = 54 V, VDGND = VAGND, DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn = 0. Positive currents are into
pins. RS = 0.200 Ω, to KSENSA (SEN1 or SEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to KSENSD
(SEN7 or SEN8). Typical values are at 25 °C. All voltages are with respect to AGND unless otherwise noted. Operating
registers loaded with default values unless otherwise noted.
0
20
40
60
80
Temperature (qC)
100
120
140
D006
Figure 6. SENSE Pin Bias Current vs Temperature
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Typical Characteristics (continued)
Conditions are –40 < TJ < 125 °C unless otherwise noted.VVDD = 3.3 V, VVPWR = 54 V, VDGND = VAGND, DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn = 0. Positive currents are into
pins. RS = 0.200 Ω, to KSENSA (SEN1 or SEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to KSENSD
(SEN7 or SEN8). Typical values are at 25 °C. All voltages are with respect to AGND unless otherwise noted. Operating
registers loaded with default values unless otherwise noted.
320
34
Idiscovery_low
Idiscovery_high
300
30
280
26
RDET (k:)
IDRAIN (PA)
260
240
220
200
22
18
14
180
15 k:
19 k:
26.5 k:
33 k:
10
160
6
140
120
-40
-20
0
20
40
60
80
Temperature (qC)
100
120
2
-40
140
26
25.8
25.6
VCLASS (V)
VPORT (V)
25.4
25.2
25
24.8
24.6
24.4
24.2
-20
0
20
40
60
80
Temperature (qC)
100
120
20
40
60
80
Temperature (qC)
100
120
140
D008
19.5
19.4
19.3
19.2
19.1
19
18.9
18.8
18.7
18.6
18.5
18.4
18.3
18.2
18.1
18
140
-40 qC
25 qC
125 qC
0
5
10
15
20
D009
Figure 9. Discovery Open Circuit Voltage vs Temperature
25 30 35
ICLASS (mA)
40
45
50
55
D010
Figure 10. Classification Voltage vs ICLASS and Temperature
9.5
78
-40 qC
25 qC
125 qC
9.4
9.3
76.4
9.2
75.6
9.1
74.8
9
8.9
74
73.2
8.8
72.4
8.7
71.6
8.6
70.8
8.5
0
0.4
0.8
1.2
1.6
2
2.4
IMARK (mA)
2.8
3.2
3.6
Class ILIM
Mark ILIM
77.2
ILIM (mA)
VMARK (V)
0
Figure 8. Discovery Resistance Measurement vs
Temperature
Figure 7. Discovery Currents vs Temperature
24
-40
-20
D007
4
70
-40
-20
D011
Figure 11. Mark Voltage vs IMARK and Temperature
0
20
40
60
80
Temperature (qC)
100
120
140
D012
Figure 12. Classification and Mark Current Limit vs
Temperature
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Typical Characteristics (continued)
Conditions are –40 < TJ < 125 °C unless otherwise noted.VVDD = 3.3 V, VVPWR = 54 V, VDGND = VAGND, DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn = 0. Positive currents are into
pins. RS = 0.200 Ω, to KSENSA (SEN1 or SEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to KSENSD
(SEN7 or SEN8). Typical values are at 25 °C. All voltages are with respect to AGND unless otherwise noted. Operating
registers loaded with default values unless otherwise noted.
2.4
2.34
2.28
2.16
VGATE (V)
VPORT (V)
2.22
2.1
2.04
1.98
1.92
1.86
1.8
-40
-20
0
20
40
60
80
Temperature (qC)
100
120
140
11.6
11.58
11.56
11.54
11.52
11.5
11.48
11.46
11.44
11.42
11.4
11.38
11.36
11.34
11.32
11.3
-40
57.5
57.5
57.4
57.4
57.3
57.3
57.2
57.2
57.1
57
56.9
56.8
120
56.5
-40
140
0
20
40
60
80
Temperature (qC)
100
120
140
IPORT Measurement (mA)
780
779
778
777
776
775
774
773
772
771
770
769
768
767
766
765
-40
-20
D017
Figure 17. Port Current ADC Measurement (100mA) vs
Temperature
16
140
D014
0
20
40
60
80
Temperature (qC)
100
120
140
D016
Figure 16. VPWR Voltage ADC Measurement vs
Temperature
IPORT Measurement (mA)
-20
-20
D015
Figure 15. Port Voltage ADC Measurement vs Temperature
101
100.9
100.8
100.7
100.6
100.5
100.4
100.3
100.2
100.1
100
99.9
99.8
99.7
99.6
99.5
-40
120
56.8
56.6
100
100
57
56.7
20
40
60
80
Temperature (q C)
40
60
80
Temperature (qC)
56.9
56.6
0
20
57.1
56.7
-20
0
Figure 14. Gate Voltage (Port On) vs Temperature
VPWR Voltage (V)
Port Voltage (V)
Figure 13. Power Good Threshold vs Temperature
56.5
-40
-20
D013
0
20
40
60
80
Temperature (qC)
100
120
140
D018
Figure 18. Port Current ADC Measurement (770mA) vs
Temperature
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Typical Characteristics (continued)
1.01
1.009
1.008
1.007
1.006
1.005
1.004
1.003
1.002
1.001
1
0.999
0.998
0.997
0.996
0.995
-40
32
31.8
31.6
31.4
PPCUT (W)
IPORT Measurement (A)
Conditions are –40 < TJ < 125 °C unless otherwise noted.VVDD = 3.3 V, VVPWR = 54 V, VDGND = VAGND, DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn = 0. Positive currents are into
pins. RS = 0.200 Ω, to KSENSA (SEN1 or SEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to KSENSD
(SEN7 or SEN8). Typical values are at 25 °C. All voltages are with respect to AGND unless otherwise noted. Operating
registers loaded with default values unless otherwise noted.
30.4
30.2
-20
0
20
40
60
80
Temperature (qC)
100
120
30
-40
140
96
62.7
95.4
62.4
94.8
62.1
94.2
61.8
93.6
61.5
61.2
91.8
91.2
60.3
90.6
20
40
60
80
Temperature (qC)
100
120
40
60
80
Temperature (qC)
100
120
140
D020
92.4
60.6
0
20
93
60.9
-20
0
Figure 20. 2-Pair PCut Threshold (30W) vs Temperature
63
60
-40
-20
D019
PPCUT (W)
PPCUT (W)
31
30.8
30.6
Figure 19. Port Current ADC Measurement (1 A) vs
Temperature
90
-40
140
-20
0
D021
Figure 21. 4-Pair PCut Threshold (60W) vs Temperature
20
40
60
80
Temperature (qC)
100
120
140
D022
Figure 22. 4-Pair PCut Threshold (90W) vs Temperature
426
426
2xFBn = 0
2xFBn = 1
425.2
425.2
424.4
424.4
423.6
423.6
422.8
422.8
ILIM (mA)
ILIM-Inrush (mA)
31.2
422
421.2
422
421.2
420.4
420.4
419.6
419.6
418.8
418.8
418
-40
-20
0
20
40
60
80
Temperature (qC)
100
120
140
418
-40
-20
D023
Figure 23. Inrush Current Limit vs Temperature
0
20
40
60
80
Temperature (qC)
100
120
140
D024
Figure 24. 1x Mode (2xFBn = 0) Current Limit vs
Temperature
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Typical Characteristics (continued)
Conditions are –40 < TJ < 125 °C unless otherwise noted.VVDD = 3.3 V, VVPWR = 54 V, VDGND = VAGND, DGND, KSENSA,
KSENSB, KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn = 0. Positive currents are into
pins. RS = 0.200 Ω, to KSENSA (SEN1 or SEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to KSENSD
(SEN7 or SEN8). Typical values are at 25 °C. All voltages are with respect to AGND unless otherwise noted. Operating
registers loaded with default values unless otherwise noted.
1.25
1.249
1.248
1.246
IPort (A)
ILIM (A)
1.247
1.245
1.244
1.243
1.242
1.241
1.24
-40
-20
0
20
40
60
80
Temperature (qC)
100
120
140
1.75
1.7
1.65
1.6
1.55
1.5
1.45
1.4
1.35
1.3
1.25
1.2
1.15
1.1
1.05
1
-40
-20
0
20
D025
Figure 25. 2x Mode (2xFBn = 1) Current Limit vs
Temperature
40
60
80
Temperature (qC)
100
120
140
D026
Figure 26. ISHORT Threshold vs Temperature
112
0.55
111
ALTIRn = 0
ALTIRn = 1
0.5
110
0.45
109
108
0.4
107
IPORT (A)
RVPWR-DRAIN (k:)
2xFBn = 0
2xFBn = 1
106
105
104
0.35
0.3
0.25
103
0.2
102
0.15
101
100
-40
0.1
-20
0
20
40
60
80
Temperature (qC)
100
120
140
0
Figure 27. ROFF (VPWR to DRAIN) vs Temperature
2xFBn =0, ALTFBn = 0
2xFBn =0, ALTFBn = 1
0.45
IPORT (A)
IPORT (A)
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0
6
12
18
24
30
36
VDRAIN (V)
42
48
18
1.3
1.2
1.1
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
24
30
36
VPORT (V)
42
48
54
D028
2xFBn =1, ALTFBn = 0
2xFBn =1, ALTFBn = 1
0
54
6
D029
Figure 29. 1x Mode (2xFBn = 0) Current Foldback vs Drain
Voltage
18
12
Figure 28. Inrush Current Foldback vs Port Voltage
0.55
0.5
6
D027
12
18
24
30
36
VDRAIN (V)
42
48
54
D030
Figure 30. 2x Mode (2xFBn = 1) Current Foldback vs Drain
Voltage
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8 Parameter Measurement Information
8.1 Timing Diagrams
trSDA
SDAI/
SDAO
tfSDA
tLOW
tr
tfo
tf
tSU,DAT
tBUF
SCL
tHD,STA
tHIGH
tHD,DAT
Start Condition
tSU,STO
tSU,STA
Stop Condition
Start Condition
Repeated
Start Condition
Figure 31. I2C Timings
SPACE
VLIM
VCUT
SEN
0V
GATE
0V
tOVLD
Figure 32. Overcurrent Fault Timing
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Timing Diagrams (continued)
Port turn-on
Class
VCLASS
Four-point
detection
VMARK
VPORT
Mark
0V
tCLE-1
tDET
tpon
Figure 33. 2-Pair Detection, 1-Event Classification and Turn On
SPACE
Port turn-on
VCLASS
Class
Four-point
detection
VMARK
VPORT
Mark
0V
tDET
tCLE-1
tME
tpon
tCLE
Figure 34. 2-Pair Detection, 3-Event Classification and Turn On
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Timing Diagrams (continued)
Port turn-on
Primary
Four-point
Detection
3 Finger Classification
VCLASS
VMARK
VPORT - Alt A
tCLE-1
0V
tME
Mark
Port turn-on
tCLE
tDET
Secondary
Four-point
Detection
VPORT - Alt B
0V
tDET
tpon
tCC
tSTART
Connection
Check
Figure 35. 4-Pair Single Signature Detection, 3-Event Classification and Turn On
Port turn-on
Primary
Four-point
Detection
5 -Finger Classification
VCLASS
VMARK
VPORT - Alt A
tCLE-1
0V
tME
tCLE
tDET
Mark
Port turn-on
Secondary
Four-point
Detection
VPORT - Alt B
0V
tDET
tCC
tpon
Connection
Check
tSTART
Figure 36. 4-Pair Single Signature Detection, 5-Event Classification and Turn On
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Timing Diagrams (continued)
Port turn-on
VCLASS
Class
Primary
Four-point
Detection
VMARK
VPORT - Alt A
tCLE-1
0V
tDET
tDET
tME
Mark
Port turn-on
tCLE
Parallel
Four-point
Detection
VPORT - Alt B
VCLASS
Class
VMARK
0V
tDET
tCC
Connection
Check
tpon
tDET
tSTART
tCLE-1
tME
Mark
tCLE
Figure 37. 4-Pair Dual Signature Detection, 3-Event Classification and Turn On
SPACE
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9 Detailed Description
9.1 Overview
The TPS23881 is an eight-channel PSE for power over Ethernet applications. Each of the eight channels
provides detection, classification, protection, and shutdown in compliance with the IEEE 802.3bt standard.
Basic PoE features include the following:
• Performs high-reliability 4-point load detection
• Performs classification including type-3/4 (three, four or five -fingers) of up to Class 8 loads
• Recognizes single signature and dual signature PDs
• Enables power with protective fold-back current limiting, and an adjustable PCUT threshold
• Shuts down during faults such as overcurrent or outputs shorts
• Performs a maintain power signature function to ensure power is removed if the load is disconnected
• Undervoltage lockout occurs if VPWR falls below VPUV_F (typical 26.5 V).
Enhanced features include the following:
• Programable SRAM memory
• Dedicated 14-bit integrating current ADCs per port
• Port re-mapping capability
• 8- and 16-bit access mode selectable
• 1- and 3-bit port shutdown priority
9.1.1 Operating Modes
9.1.1.1 Auto
The port performs detection and classification (if valid detection occurs) continuously. Registers are updated
each time a detection or classification occurs. The port power is automatically turned on based on the Power
Allocation settings in register 0x29 if a valid classification is measured.
9.1.1.2 Autonomous
Unlike Auto mode, which still requires a host to initialize the TPS23881 operation through a series of I2C
commands, there is no host or I2C communication required when the device is in configured in Autonomous
mode.
During power up, the resistance on the AUTO pin (RAUTO) is measured, and the device is pre-configured
according to Table 15. The port automatically performs detection and classification (if valid detection occurs)
continuously on all ports. Port power is automatically turned on based on Power Allocation settings in register
0x29 if a valid classification is measured.
For applications that still require port telemetry, the I2C functionality is still supported in Autonomous mode.
NOTE
A 10 nF capacitor is required in parallel with RAUTO to ensure stability in the Autonomous
mode selection.
The Auto pin resistance (RAUTO) will not be measured following a device reset (assertion
of the RESET pin or RESAL bit in register 0x1A). The device wil only measured (RAUTO)
and pre-configure the internal registers during power up (VVPWR and VVDD rising above
their respective UVLO thresholds).
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Overview (continued)
NOTE
The device SRAM will need to be programmed in order to support applications that desire
to remove a device from Autonomous mode after having initially powered up in
Autonomous mode.
A device running from the internal ROM (SRAM unprogrammed) in Autonomous mode will
turn off and automatically resume discovery and power on any valid loads following the
assertion of the RESET pin, I2C register 0x1A RESAL or RESPn bits, or a mode off
command. Whereas a device running in Autonomous mode with the SRAM programmed
will turn off and remain inactive until the host re-enables the port(s) through the I2C bus.
9.1.1.3 Semiauto
The port performs detection and classification (if valid detection occurs) continuously. Registers are updated
each time a detection or classification occurs. The port power is not automatically turned on. A Power Enable
command is required to turn on the port.
9.1.1.4 Manual/Diagnostic
The use of this mode is intended for system diagnostic purposes only in the event that ports cannot be
powered in accordance with the IEEE 802.3bt standard from Semiauto or Auto modes.
The port performs the functions as configured in the registers. There is no automatic state change. Singular
detection and classification measurements will be performed when commanded. Ports will be turned on
immediately after a Power Enable command without any detection or classification measurements. Even though
multiple classification events may be provided, the port voltage will reset immediately after the last finger,
resetting the PD.
9.1.1.5 Power Off
The port is powered off and does not perform a detection, classification, or power-on. In this mode, Status and
Enable bits for the associated port are reset.
SPACE
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Overview (continued)
9.1.2 Channel versus Port Terminology
Throughout this document the use of the terms port and channel will be used regularly, but these terms are not
interchangeable. Instead the term port will be used to refer to the PSE PI (Power Interface), which is most
commonly associated with a RJ45 connector, whereas the term channel will be used to refer to the individual
power path or paths associated with each port.
Previous PSE devices commonly equated the number of controlled outputs as ports as each output would be
dedicated to providing power on either the ALT-A or Alt-B pair set of a RJ45 jack/Ethernet port. However, with
the adoption of 4-Pair power delivery sending power down both the ALT-A and ALT-B pair sets, there is now a
need to differentiate between 2-pair and 4-pair capable PoE ports. Even more so, with the requirement to provide
individual current limiting per pair set, any 4-pair port will now use two channels per 4-pair port to ensure safe
and reliable delivery of power down each pair set.
As the TPS23881 is an 8-channel PSE controller. It can be configured to support up to eight 2-pair PoE ports or
four 4-pair PoE ports, or any combination thereof where each 2-pair port accounts for one channel, and each 4pair port accounts for 2 channels.
SPACE
9.1.3 Requested Class versus Assigned Class
The requested class is the classification the PSE measures during mutual identification prior to turnon, whereas
the assigned class is the classification level the channel was powered on with based on the power allocation
setting in register 0x29h. In most cases where the power allocation equals or exceeds the requested class, the
requested and assigned classes will be the same. However, in the case of power demotion, these values will
differ.
For example: If a Class 8 PD is connected to a 60 W (Class 6) limited PSE port, the requested class reports
"Class 8", while the assigned class reports "Class 6".
The requested classification results are available in registers 0x0C-0F
The assigned classification results are available in registers 0x4C-4F
NOTE
There is no Assigned Class assigned for ports/channels powered out of Manual/Diagnostic
mode.
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Overview (continued)
9.1.4 Power Allocation and Power Demotion
The Power Allocation settings in register 0x29 sets the maximum power level a port will power on. Settings for
each Class level from 2-pair 4 W (Class 1) up to 4-pair 90 W (Class 8) have been provided to maximize system
design flexibility.
NOTE
The Power Allocation settings in register 0x29 do not set the power limit for a given port.
The port and channel power limiting is configured with the 2P (registers 0x1E- x 21) and
4P (0x2A - x2B) policing registers
During a turn on attempt, if a PD presents a classification level greater than the power allocation setting for a
port, the TPS23881 limits the number of classification fingers presented to the PD prior to turn on based on the
power allocation settings in register 0x29. This behavior is called Power Demotion as it is the number of fingers
presented to the PD that sets the maximum level of power the PD is allowed to draw before the PSE is allowed
to disable it.
NOTE
Power Demotion on a port is limited to the Type boundaries as the only means of
communication from the PSE to the PD is the number of classification fingers prior to turn
on.
1 finger = 15.4 W, 3 fingers = 30 W, 4 fingers = 60 W, and 5 fingers = 90W
Table 1. Single Signature PD Power Demotion Table
Assigned Class Value (based on the PD connected at the port)
Power Allocation
Register 0x29
Class 3 PD
Class 4 PD
Class 5 PD
Class 6 PD
Class 7 PD
Class 8 PD
4-Pair 15W
Class 3
Class 3
Class 3
Class 3
Class 3
Class 3
4-Pair 30W
Class 3
Class 4
Class 4
Class 4
Class 4
Class 4
4-Pair 45W
Class 3
Class 4
Class 5
Class 4
Class 5
Class 5
4-Pair 60W
Class 3
Class 4
Class 5
Class 6
Class 6
Class 6
4-Pair 75W
Class 3
Class 4
Class 5
Class 6
Class 7
Class 6
4-Pair 90W
Class 3
Class 4
Class 5
Class 6
Class 7
Class 8
Table 2. Dual Signature PD Power Demotion Table
Power Allocation
Register 0x29
Assigned Class Value (based on the PD connected at the port)
Class 3D PD
Class 4D PD
Class 5D PD
Odd Channel
(Primary)
Even Channel
(Secondary)
Odd Channel
(Primary)
Even Channel
(Secondary)
Odd Channel
(Primary)
Even Channel
(Secondary)
4-Pair 15W
Class 3
Insufficient Power
Class 3
Insufficient Power
Class 3
Insufficient Power
4-Pair 30W
Class 3
Class 3
Class 4
Insufficient Power
Class 4
Insufficient Power
4-Pair 45W
Class 3
Class 3
Class 4
Class 3
Class 5D
Insufficient Power
4-Pair 60W
Class 3
Class 3
Class 4
Class 4
Class 5D
Class 3
4-Pair 75W
Class 3
Class 3
Class 4
Class 4
Class 5D
Class 4
4-Pair 90W
Class 3
Class 3
Class 4
Class 4
Class 5D
Class 5D
NOTE
Class "X-D" Dual Signature PDs present as Class "X" on each alterative pairset. For
example: a "Class 4D" PD would present as Class 4 on both the Alterative A and
Alternative B pairsets.
26
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9.2 Functional Block Diagram
VDD
VPWR
LDO
NC
NC
NC
NC
1/3
2/3
2/3
1/3
VPWR Divider
CLK OK
Internal Oscillator
CLK
to blks
Clock Distribution
VPWR
VDD
UVLO
Internal Rails
Good
VPWR
CPU Watchdog
CLK OK
PG
RESETB
RST Block
OSS
Firmware Controlled
Update from register File
RST
to blks
PG
Port 2-8 Analog Control Functions
VPWR
MCU
Port 1 Analog Control Functions
PD
LOAD
Program Memory
OSS/
POR
Foldback Schedulers
DRAINx
Enable
Gm
DRIVER
Fuse-able
Disconnect
dv/dt ramping control
Timers
CPU
7 bit address
Select
FW Registers
Prog
Mem
Bus
SFR
BUS
I2C Interface
Rapid Overload recovery
IRAM
Bus
SFR
With BIST
SCL
ROM
2X Power
Bus IF
SENx
Class Port Voltage Control
CPU SRAM
IPORT
14 Bit ADC
(Current)
RSENSE
KSENSEx
320Hz LPF
GND
ICLASS
BIT
REMAP
External Data
Memory Bus
GATEx
Class Current Limit
SCL Watchdog
INT
Fast Ishort Protection
RANGE
SELECT
SDAI
SDAO
Scan + Digital
Test
Memory BIST
A1-A4
DISCRETE IO CONDITIONERS
Ilim
SRAM
Variable Averager
Register File
Interrupt
Controller
Common Functions for Ports 5-8
OSS
Load at Power
up into holding
latches
Analog TRIM
14 Bit ADC
(Voltage)
RANGE SELECT
Common Functions for Ports1-4
Vdisco
Vport
Vds
VEE
Temp
BIT
V48
PORT DIFF
AMP
4:1 MUX
PTAT DIODES
Analog BIT MUX
V48
DRAIN1-4
IDET
Variable Averager
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9.3 Feature Description
9.3.1 Port Remapping
The TPS23881 provides port remapping capability, from the logical ports to the physical channels and pins.
The remapping is between any channel of a 4-port group (1 to 4, 5 to 8).
The following example is applicable to 0x26 register = 00111001, 00111001b.
• Logical port 1 (5) ↔ Physical channel 2 (6)
• Logical port 2 (6) ↔ Physical channel 3 (7)
• Logical port 3 (7) ↔ Physical channel 4 (8)
• Logical port 4 (8) ↔ Physical channel 1 (5)
NOTE
The device ignores any remapping command unless all four ports are in off mode.
If the TPS23881 receives an incorrect configuration, it ignores the incorrect configuration and retains the
previous configuration. The ACK is sent as usual at the end of communication. For example, if the same
remapping code is received for more than one port, then a read back of the Re-Mapping register (0x26) would be
the last valid configuration.
Note that if an IC reset command (1Ah register) is received, the port remapping configuration is kept unchanged.
However, if there is a Power-on Reset or if the RESET pin is activated, the Re-Mapping register is reinitialized to
a default value.
9.3.2 Port Power Priority
The TPS23881 supports 1- and 3-bit shutdown priority, which are selected with the MbitPrty bit of General Mask
register (0x17).
The 1-bit shutdown priority works with the Port Power Priority (0x15) register. An OSSn bit with a value of 1
indicates that the corresponding port is treated as low priority, while a value of 0 corresponds to a high priority.
As soon as the OSS input goes high, the low-priority ports are turned off.
The 3-bit shutdown priority works with the Multi Bit Power Priority (0x27/28) register, which holds the priority
settings. A port with “000” code in this register has highest priority. Port priority reduces as the 3-bit value
increases, with up to 8 priority levels. See Figure 38.
The multi bit port priority implementation is defined as the following:
• OSS code ≤ Priority setting (0x27/28 register): Port is disabled
• OSS code > Priority setting (0x27/28 register): Port remains active
Shutdown Code
START bits
3.3 V
OSS
SC 2
IDLE
SC 1
SC 0
0V
IDLE
tf_OSS
tOSS_IDL
tbit_OSS
one-bit
duration
tr_OSS
tOSS_OFF
GATE
Figure 38. Multi Bit Priority Port Shutdown if Lower-Priority Port
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Feature Description (continued)
NOTE
Prior to setting the MbitPrty bit from 0 to 1, make sure the OSS input is in the idle (low)
state for a minimum of 200 µs, to avoid any port misbehavior related to loss of
synchronization with the OSS bit stream.
NOTE
The OSS input has an internal 1-µs to 5-µs deglitch filter. From the idle state, a pulse with
a longer duration is interpreted as a valid start bit. Ensure that the OSS signal is noise
free.
NOTE
To ensure both channels of a 4-pair port are disabled during and OSS event, make sure
both channel have the same configurations in the 0x15 or 0x27/28 registers.
9.3.3 Analog-to-Digital Converters (ADC)
The TPS23881 features 10 multi-slope integrating converters. Each of the first eight converters is dedicated to
current measurement for one channel and operate independently to perform measurements during classification
and when the channel is powered on. When the channel is powered, the converter is used for current (100-ms
averaged) monitoring, power policing, and DC disconnect. Each of the last two converters are shared within a
group of four channels for discovery (16.6-ms averaged), port powered voltage monitoring, power-good status,
and FET short detection. These converters are also used for general-purpose measurements including input
voltage (1 ms) and die temperature.
The ADC type used in the TPS23881 differs from other similar types of converters in that the ADCs continuously
convert while the input signal is sampled by the integrator, providing inherent filtering over the conversion period.
The typical conversion time of the current converters is 800 µs, while the conversion time is 1 ms for the other
converters. Powered-device detection is performed by averaging 16 consecutive samples which provides
significant rejection of noise at 50-Hz or 60-Hz line frequency. While a port is powered, digital averaging provides
a channel current measurement integrated over a 100-ms time period. Note that an anti-aliasing filter is present
for powered current monitoring.
NOTE
During powered mode, current conversions are performed continuously. Also, in powered
mode, the tSTART timer must expire before any current or voltage ADC conversion can
begin.
9.3.4 I2C Watchdog
An I2C Watchdog timer is available on the TPS23881 device. The timer monitors the I2C, SCL line for clock
edges. When enabled, a timeout of the watchdog resets the I2C interface along with any active ports. This
feature provides protection in the event of a hung software situation or I2C bus hang-up by slave devices. In the
latter case, if a slave is attempting to send a data bit of 0 when the master stops sending clocks, then the slave
my drive the data line low indefinitely. Because the data line is driven low, the master cannot send a STOP to
clean up the bus. Activating the I2C watchdog feature of the TPS23881 clears this deadlocked condition. If the
timer of two seconds expires, the ports latch off and the WD status bit is set. Note that WD Status will be set
even if the watchdog is not enabled. The WD status bit may only be cleared by a device reset or writing a 0 to
the WDS status bit location. The 4-bit watchdog disable field shuts down this feature when a code of 1011b is
loaded. This field is preset to 1011b whenever the TPS23881 is initially powered. See I2C WATCHDOG Register
for more details.
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Feature Description (continued)
9.3.5 Current Foldback Protection
The TPS23881 features two types of foldback mechanisms for complete MOSFET protection.
During inrush, at channel turn on, the foldback is based on the channel voltage as shown in Figure 39. Note that
the inrush current profile remains the same, regardless of the state of the 2xFBn bits in register 0x40.
After the channel is powered and the Power Good is valid, a dual-slope operational foldback is used, providing
protection against partial and total short-circuit at port output, while still being able to maintain the PD powered
during normal transients at the PSE input voltage. Note that setting the 2xFBn bit selects the 2× curve and
clearing it selects the 1× curve. See Figure 40.
In addition to the default foldback curves, the TPS23881 has individually enabled alternative foldback curves for
both inrush and powered operation. These curves have been designed to accommodate certain loads that do not
fully comply with the IEEE standard and requires additional power to be turned on or remain powered. See
Figure 39 and Figure 40.
NOTE
If using the Alternative Foldback curves (ALTIRn or ALTFBn = 1), designers need to
account for the additional power dissipation that can occur in the FETs under these
conditions.
1.3
0.55
ALTIRn = 0
ALTIRn = 1
0.5
2xFBn =0, ALTFBn = 0
2xFBn =0, ALTFBn = 1
2xFBn =1, ALTFBn = 0
2xFBn =1, ALTFBn = 1
1.2
1.1
0.45
1
0.4
0.9
0.8
IPORT (A)
IPORT (A)
0.35
0.3
0.25
0.7
0.6
0.5
0.2
0.4
0.15
0.3
0.1
0.2
0.05
0.1
0
0
0
3
6
9
12
15
18
21
24
27
30
VPORT (V)
33
36
39
42
45
48
51
54
57
0
3
6
D100
Figure 39. Foldback During Inrush (at Port Turn On): ILIM
vs Vport
9
12
15
18
21
24
27
30
VDRAIN (V)
33
36
39
42
45
48
51
54
57
D200
Figure 40. Foldback When the Port is Already ON: ILIM vs
Vdrain
9.4 Device Functional Modes
9.4.1 Detection
To eliminate the possibility of false detection, the TPS23881 uses a TI proprietary 4-point detection method to
determine the signature resistance of the PD device. A false detection of a valid 25-kΩ signature can occur with
2-point detection type PSEs in noisy environments or if the load is highly capacitive.
Detection 1 and Detection 2 are merged into a single detection function which is repeated. Detection 1 applies I1
(160 μA) to a channel, waits approximately 60 ms, then measures the channel voltage (V1) with the integrating
ADC. Detection 2 then applies I2 (270 μA) to the channel, waits another approximately 60 ms, then measures the
channel voltage again (V2). The process is then repeated a second time to capture a third (V3) and fourth (V4)
channel voltage measurements. Multiple comparisons and calculations are performed on all four measurement
point combinations to eliminate the effects of a nonlinear or hysteretic PD signature. The resulting channel
signature is then sorted into the appropriate category.
NOTE
The detection resistance measurement result is also available in the Channel Detect
Resistance registers (0x44 - 0x47).
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Device Functional Modes (continued)
9.4.2 Connection Check
For 4-pair configured ports, the TPS23881 performs a connection check immediately after it measures a valid
detection on either channel. During connection check both channels are probed to determine if a single signature
or dual signature load is present on the port, and the results of this measurement are provided in the lower nibble
(4 bits) of register 0x1C. The accurate determination of a single signature or dual signature is critical to the PSEs
management of the port.
Secondary
Four-point
Detection
Primary
Four-point
Detection
VPORT - Alt A
0V
tDET
VPORT - Alt B
0V
tDET
tCC
Connection
Check
Figure 41. 4-Pair Port, Detection and Connection Check Waveforms with a Single Signature Load
Parallel
Four-point
Detection
Primary
Four-point
Detection
VPORT - Alt A
0V
tDET
tDET
VPORT - Alt B
0V
tDET
tCC
Connection
Check
Figure 42. 4-Pair Port, Detection and Connection Check Waveforms with a Dual Signature Load
9.4.3 Classification
Hardware classification (class) is performed by supplying a voltage and sampling the resulting current. To
eliminate the high power of a classification event from occurring in the power controller chip, the TPS23881 uses
the external power FET for classification.
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Device Functional Modes (continued)
During classification, the voltage on the gate node of the external MOSFET is part of a linear control loop. The
control loop applies the appropriate MOSFET drive to maintain a differential voltage between VPWR and DRAIN
of 18.5 V. During classification the voltage across the sense resistor in the source of the MOSFET is measured
and converted to a class level within the TPS23881. If a load short occurs during classification, the MOSFET
gate voltage reduces to a linearly controlled, short-circuit value for the duration of the class event.
Classification results are read through the I2C Detection Event and Channel-n Discovery Registers. The
TPS23881 also supports 1, 3, 4, or 5 finger classification for PDs ranging from Class 0 through Class 8, using
the Power Enable and Port Power Allocation registers.
9.4.4 DC Disconnect
Disconnect is the automated process of turning off power to the port. When the port is unloaded or at least falls
below minimum load, it is required to turn off power to the port and restart detection. In DC disconnect, the
voltage across the sense resistors is measured. When enabled, the DC disconnect function monitors the sense
resistor voltage of a powered port to verify the port is drawing at least the minimum current to remain active. The
TDIS timer counts up whenever the port current is below the disconnect threshold (6.5 mA or 4.5 mA depending
on the port configuration). If a timeout occurs, the port is shut down and the corresponding disconnect bit in the
Fault Event Register is set. In the case of a PD implementing MPS (maintain Power Signature) current pulsing,
the TDIS counter is reset each time the current goes continuously higher than the disconnect threshold for at least
3 ms.
The TDIS duration is set by the TMPDO Bits of the Timing Configuration register (0x16).
NOTE
If a Class 4 or lower 4-Pair Single Signature PD is connected, the TPS23881 will
immediately power down one channel immediately after (no TMPDO timeout) the current
falls below the disconnect threshold while leaving the second channel powered. This
channel will be re-powered if the current on the remaining channel exceed 75mA.
Alterntively if the current on the remaining channel falls below the disconnect threshold for
longer than the TMPDO timeout, the port will be shut down and the corresponding
disconnect bits in the Fault Event Register are set.
NOTE
If both channels of a 4-Pair Dual Signature PD are powered, the DCDTx bit in register
0x2D is automatically set after turn on to ensure the IEEE compliant 4.5mA threshold is
used.
NOTE
If a 4-Pair Single Signature Class 5-8 PD is powered, the DCDTx bit in register 0x2D is
automatically set after turn on to ensure the IEEE compliant 4.5mA threshold is used.
9.5 I2C Programming
9.5.1 I2C Serial Interface
The TPS23881 features a 3-wire I2C interface, using SDAI, SDAO, and SCL. Each transmission includes a
START condition sent by the master, followed by the device address (7-bit) with R/W bit, a register address byte,
then one or two data bytes and a STOP condition. The recipient sends an acknowledge bit following each byte
transmitted. SDAI/SDAO is stable while SCL is high except during a START or STOP condition.
Figure 43 and Figure 44 show read and write operations through I2C interface, using configuration A or B (see
Table 25 for more details). The parametric read operation is applicable to ADC conversion results. The
TPS23881 features quick access to the latest addressed register through I2C bus. When a STOP bit is received,
the register pointer is not automatically reset.
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I2C Programming (continued)
It is also possible to perform a write operation to many TPS23881 devices at the same time. The slave address
during this broadcast access is 0x7F, as shown in PIN STATUS Register. Depending on which configuration (A
or B) is selected, a global write proceeds as following:
• Config A: Both 4-port devices (1 to 4 and 5 to 8) are addressed at same time.
• Config B: The whole device is addressed.
Slave Address
R/W=1
SDAO
Data from
Slave to Host
Stop Bit
Command Code
D7 D6 D5 D4 D3 D2 D1 D0
1 A4 A3 A2 A1 A0 R/W
NAck Bit
Start Bit
Slave Address
R/W=0
0
R/W
Bit
Ack Bit
C7 C6 C5 C4 C3 C2 C1 C0
1 A4 A3 A2 A1 A0 R/W
Repeated
Start Bit
0
Address
Pins
Ack Bit
SDAI
R/W
Bit
Ack Bit
Address
Pins
Non-Parametric
Read Cycle
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
LSByte Data from
Slave to Host
MSByte Data from
Slave to Host
D7 D6 D5 D4 D3 D2 D1 D0
SDAO
Address
Pins
Stop Bit
Slave Address
R/W=1
D7 D6 D5 D4 D3 D2 D1 D0
NAck Bit
Command Code
1 A4 A3 A2 A1 A0 R/W
Ack Bit
0
R/W
Bit
Ack Bit
Start Bit
Slave Address
R/W=0
C7 C6 C5 C4 C3 C2 C1 C0
Repeated
Start Bit
1 A4 A3 A2 A1 A0 R/W
Address
Pins
Ack Bit
0
SDAI
R/W
Bit
Ack Bit
Address
Pins
Parametric
Read Cycle
D7 D6 D5 D4 D3 D2 D1 D0
R/W
Bit
D7 D6 D5 D4 D3 D2 D1 D0
Command Code
Data from
Host to Slave
Stop Bit
Start Bit
Slave Address
R/W=0
C7 C6 C5 C4 C3 C2 C1 C0
Ack Bit
1 A4 A3 A2 A1 A0 R/W
Ack Bit
0
SDAI
Ack Bit
Write Cycle
SDAO
SDAO
D7 D6 D5 D4 D3 D2 D1 D0
1 A4 A3 A2 A1 A0 R/W
Slave Address
R/W=1
Data from
Slave to Host
Stop Bit
Start Bit
0
R/W
Bit
NAck Bit
SDAI
Address
Pins
Ack Bit
Quick Read Cycle
(latest addressed register)
D7 D6 D5 D4 D3 D2 D1 D0
Figure 43. I2C interface Read and Write Protocol – Configuration A
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I2C Programming (continued)
SDAO
Repeated
Start Bit
Ack Bit
Start Bit
Slave Address
R/W=0
0
Command Code
D7 D6 D5 D4 D3 D2 D1 D0
Port 4-1 Data from
Slave to Host
Port 8-5 Data from
Slave to Host
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
Port 4-1
LSByte Data from
Slave to Host
Port 4-1
MSByte Data from
Slave to Host
R/W
Bit
1 A4 A3 A2 A1 0
R/W
Slave Address
R/W=1
D7 D6 D5 D4 D3 D2 D1 D0
...
Stop Bit
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
R/W
Bit
C7 C6 C5 C4 C3 C2 C1 C0
D7 D6 D5 D4 D3 D2 D1 D0
Command Code
Port 4-1 Data from
Host to Slave
D7 D6 D5 D4 D3 D2 D1 D0
Port 8-5 Data from
Host to Slave
Stop Bit
1 A4 A3 A2 A1 0 R/W
Slave Address
R/W=0
Ack Bit
D7 D6 D5 D4 D3 D2 D1 D0
Ack Bit
Start Bit
Port 8-5
MSByte Data from
Slave to Host
Ack Bit
0
Port 8-5
LSByte Data from
Slave to Host
Ack Bit
Address
Pins
Write Cycle
D7 D6 D5 D4 D3 D2 D1 D0
...
SDAO
SDAI
D7 D6 D5 D4 D3 D2 D1 D0
Ack Bit
SDAI
NAck Bit
SDAO
Ack Bit
C7 C6 C5 C4 C3 C2 C1 C0
1 A4 A3 A2 A1 0 R/W
Ack Bit
0
SDAI
Address
Pins
Ack Bit
R/W
Bit
Address
Pins
Parametric
Read Cycle
D7 D6 D5 D4 D3 D2 D1 D0
Stop Bit
R/W
Slave Address
R/W=1
NAck Bit
1 A4 A3 A2 A1 0
Ack Bit
0
Command Code
Ack Bit
Start Bit
Slave Address
R/W=0
Ack Bit
C7 C6 C5 C4 C3 C2 C1 C0
1 A4 A3 A2 A1 0 R/W
Repeated
Start Bit
0
R/W
Bit
Address
Pins
Ack Bit
SDAI
R/W
Bit
Address
Pins
Ack Bit
Non-Parametric
Read Cycle
SDAO
Figure 44. I2C interface Read and Write Protocol – Configuration B
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9.6 Register Maps
9.6.1 Complete Register Set
Table 3. Main Registers
2
Register or
Command Name
IC
R/W
Data
Byte
RST State
00h
INTERRUPT
RO
1
1000,0000b (1)
SUPF
STRTF
IFAULT
CLASC
DETC
DISF
PGC
PEC
01h
INTERRUPT MASK
R/W
1
1000,0000b
1110,0100b (2)
SUMSK
STMSK
IFMSK
CLMSK
DEMSK
DIMSK
PGMSK
PEMSK
PGC1
PEC4
Cmd
Code
Bits Description
INTERRUPTS
EVENT
02h
03h
04h
05h
POWER EVENT
DETECTION EVENT
06h
FAULT EVENT
07h
08h
09h
0Ah
0Bh
START/ILIM EVENT
SUPPLY/FAULT EVENT
RO
1
CoR
1
RO
1
CoR
1
RO
1
CoR
1
RO
1
CoR
1
RO
1
CoR
1
0000,0000b
0000,0000b
0000,0000b
0000,0000b
0111,0000b
(3)
Power Good status change
PGC4
PGC3
PGC2
Power Enable status change
PEC3
Classification
CLSC4
CLSC3
CLSC2
CLSC1
DETC4
DETC3
Disconnect occurred
DISF4
DISF3
ILIM4
ILIM3
TSD
VDUV
PEC2
PEC1
DETC2
DETC1
Detection
PCUT fault occurred
DISF2
DISF1
PCUT4
PCUT3
ILIM2
ILIM1
STRT4
STRT3
STRT2
STRT1
VDWRN
VPUV
PCUT34
PCUT12
OSSE
RAMFLT
ILIM fault occurred
PCUT2
PCUT1
START fault occurred
STATUS
0Ch
CHANNEL 1 DISCOVERY
RO
1
0000,0000b
Requested CLASS Channel 1
DETECT Channel 1
0Dh
CHANNEL 2 DISCOVERY
RO
1
0000,0000b
Requested CLASS Channel 2
DETECT Channel 2
0Eh
CHANNEL 3 DISCOVERY
RO
1
0000,0000b
Requested CLASS Channel 3
DETECT Channel 3
0Fh
CHANNEL 4 DISCOVERY
RO
1
0000,0000b
Requested CLASS Channel 4
10h
POWER STATUS
RO
1
0000,0000b
PG4
PG3
PG2
PG1
PE4
PE3
PE2
PE1
11h
PIN STATUS
RO
1
AUTO,A[4:0],0,0
AUTO
SLA4
SLA3
SLA2
SLA1
SLA0
Rsvd
Rsvd
12h
OPERATING MODE
R/W
1
0000,0000b
13h
DISCONNECT ENABLE
R/W
1
0000 ,1111b
Rsvd
Rsvd
Rsvd
Rsvd
DCDE4
DCDE3
DCDE2
14h
DETECT/CLASS ENABLE
R/W
1
0000,0000b
CLE4
CLE3
CLE2
CLE1
DETE4
DETE3
DETE2
DETE1
15h
PWRPR/PCUT DISABLE
R/W
1
0000,0000b
OSS4
OSS3
OSS2
OSS1
DCUT4
DCUT3
DCUT2
DCUT1
16h
TIMING CONFIG
R/W
1
0000,0000b
17h
GENERAL MASK
R/W
1
1000,0000b
Rsvd
nbitACC
MbitPrty
CLCHE
DETECT Channel 4
CONFIGURATION
(1)
(2)
(3)
Channel 4 Mode
Channel 3 Mode
TLIM
INTEN
Channel 2 Mode
TSTART
TOVLD
Channel 1 Mode
DCDE1
TMPDO
DECHE
Rsvd
SUPF bit reset state shown is at Power up only
Register 0x01 is initialized to 0xE4h if the device powers up in Autonomous mode
VDUV, VPUV and VDWRN bits reset state shown is at Power up only
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Register Maps (continued)
Table 3. Main Registers (continued)
Register or
Command Name
I2C
R/W
Data
Byte
RST State
18h
DETECT/CLASS Restart
WO
1
0000,0000b
RCL4
RCL3
RCL2
RCL1
RDET4
RDET3
RDET2
RDET1
19h
POWER ENABLE
WO
1
0000,0000b
POFF4
POFF3
POFF2
POFF1
PWON4
PWON3
PWON2
PWON1
1Ah
RESET
WO
1
0000,0000b
CLRAIN
CLINP
Rsvd
RESAL
RESP4
RESP3
RESP2
RESP1
Cmd
Code
Bits Description
PUSH BUTTONS
GENERAL/SPECIALIZED
1Bh
ID
RO
1
0101,0101b
1Ch
AUTOCLASS and
CONNECTION CHECK
RO
1
0000,0000b
1Dh
RESERVED
R/W
1
0000,0000b
Rsrvd
1Eh
2P POLICE 1 CONFIG
R/W
1
1111,1111b
2-Pair POLICE Channel 1
1Fh
2P POLICE 2 CONFIG
R/W
1
1111,1111b
2-Pair POLICE Channel 2
20h
2P POLICE 3 CONFIG
R/W
1
1111,1111b
2-Pair POLICE Channel 3
21h
2P POLICE 4CONFIG
R/W
1
1111,1111b
22h
CAP MEASUREMENT (4)
R/W
1
0000,0000b
Rsvd
CDET4
Rsvd
CDET3
23h
Reserved
R/W
1
0000,0000b
Rsvd
Rsvd
Rsvd
Rsvd
RO
1
CoR
1
24h
25h
Power-on FAULT
MFR ID
AC4
AC3
AC2
IC Version
AC1
CC34_2
CC34_1
CC12_2
CC12_1
Rsvd
CDET2
Rsvd
CDET1
Rsvd
Rsvd
Rsvd
Rsvd
2-Pair POLICE Channel 4
0000,0000b
PF Channel 4
PF Channel 3
PF Channel 2
PF Channel 1
Physical re-map Logical Port 4
Physical re-map Logical Port 3
Physical re-map Logical Port 2
Physical re-map Logical Port 1
26h
RE-MAPPING
R/W
1
1110,0100b
27h
Multi-Bit Priority 21
R/W
1
0000,0000b
Rsvd
Channel 2
Rsvd
Channel 1
28h
Multi-Bit Priority 43
R/W
1
0000,0000b
Rsvd
Channel 4
Rsvd
Channel 3
29h
Port Power Allocation
R/W
1
0000,0000b
4P34
MC34
4P12
MC12
2Ah
4P POLICE 12 CONFIG
R/W
1
1111,1111b
4-Pair POLICE Channels 1 and 2
2Bh
4P POLICE 34 CONFIG
R/W
1
1111,1111b
4-Pair POLICE Channels 3 and 4
2Ch
TEMPERATURE
RO
1
0000,0000b
2Dh
4P FAULT CONFIG
R/W
1
0000,0000b
2Eh
2Fh
INPUT VOLTAGE
RO
RO
2
Temperature (bits 7 to 0)
NLM34
NLM12
NCT34
0000,0000b
0000,0000b
NCT12
4PPCT34
4PPCT12
DCDT34
DCDT12
Input Voltage: LSByte
Rsvd
Rsvd
Rsvd
Rsvd
Input Voltage: MSByte (bits 13 to 8)
EXTENDED REGISTER SET – PARAMETRIC MEASUREMENT
30h
31h
32h
33h
(4)
36
Channel 1 CURRENT
Channel 1 VOLTAGE
RO
RO
RO
RO
2
2
0000,0000b
0000,0000b
Channel 1 Current: LSByte
0000,0000b
0000,0000b
Channel 1 Current: MSByte (bits 13 to 8)
Channel 1 Voltage: LSByte
Rsvd
Rsvd
Channel 1 Voltage: MSByte (bits 13 to 8)
Capacitance Measurement is only supported if SRAM code is programmed
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Table 4. Main Registers
Cmd
Code
34h
35h
36h
37h
38h
39h
3Ah
3Bh
3Ch
3Dh
3Eh
3Fh
Register or
Command Name
Channel 2 CURRENT
Channel 2 VOLTAGE
Channel 3 CURRENT
Channel 3 VOLTAGE
Channel 4 CURRENT
Channel 4 VOLTAGE
I2C R/W
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
Data
Byte
2
2
2
2
2
2
RST State
Bits Description
0000,0000b
0000,0000b
Channel 2 Current: LSByte
Rsvd
Rsvd
Channel 2 Current: MSByte (bits 13 to 8)
0000,0000b
0000,0000b
Channel 2 Voltage: LSByte
Rsvd
Rsvd
Channel 2 Voltage: MSByte (bits 13 to 8)
0000,0000b
0000,0000b
Channel 3 current: LSByte
Rsvd
Rsvd
Channel 3 Current: MSByte (bits 13 to 8)
0000,0000b
0000,0000b
Channel 3 Voltage: LSByte
Rsvd
Rsvd
Channel 3 Voltage: MSByte (bits 13 to 8)
0000,0000b
0000,0000b
Channel 4 current: LSByte
Rsvd
Rsvd
Channel 4 Current: MSByte (bits 13 to 8)
0000,0000b
Channel 4 Voltage: LSByte
0000,0000b
Rsvd
Rsvd
2xFB4
2xFB3
Channel 4 Voltage: MSByte (bits 13 to 8)
CONFIGURATION/OTHERS
40h
CHANNEL FOLDBACK
R/W
1
0000,0000b
41h
FIRMWARE REVISION
RO
1
RRRR,RRRRb
42h
I2C WATCHDOG
R/W
1
0001,0110b
43h
DEVICE ID
RO
1
0010,0010b
2xFB2
2xFB1
Rsvd
Rsvd
Rsvd
Rsvd
Firmware Revision
Rsvd
Rsvd
Rsvd
Watchdog Disable
Device ID number
WDS
Silicon Revision number
SIGNATURE MEASUREMENTS
(1)
44h
Ch1 DETECT
RESISTANCE
RO
1
0000,0000b
Channel 1 Resistance
45h
Ch2 DETECT
RESISTANCE
RO
1
0000,0000b
Channel 2 Resistance
46h
Ch3 DETECT
RESISTANCE
RO
1
0000,0000b
Channel 3 Resistance
47h
Ch4 DETECT
RESISTANCE
RO
1
0000,0000b
Channel 4 Resistance
48h
Ch1 CAP
MEASUREMENT (1)
RO
1
0000,0000b
Channel 1 Capacitance
49h
Ch2 CAP
MEASUREMENT (1)
RO
1
0000,0000b
Channel 2 Capacitance
4Ah
Ch3 CAP
MEASUREMENT (1)
RO
1
0000,0000b
Channel 3 Capacitance
4Bh
Ch4 CAP
MEASUREMENT (1)
RO
1
0000,0000b
Channel 4 Capacitance
Capacitance Measurement is only supported if SRAM code is programmed
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Table 4. Main Registers (continued)
Register or
Command Name
Cmd
Code
I2C R/W
Data
Byte
RST State
Bits Description
ASSIGNED CHANNEL STATUS
4Ch
ASSIGNED CLASS
CHANNEL 1
RO
1
0000,0000b
Assigned CLASS Channel 1
Previous CLASS Channel 1
4Dh
ASSIGNED CLASS
CHANNEL 2
RO
1
0000,0000b
Assigned CLASS Channel 2
Previous CLASS Channel 2
4Eh
ASSIGNED CLASS
CHANNEL 3
RO
1
0000,0000b
Assigned CLASS Channel 3
Previous CLASS Channel 3
4Fh
ASSIGNED CLASS
CHANNEL 4
RO
1
0000,0000b
Assigned CLASS Channel 4
Previous CLASS Channel 4
AUTOCLASS CONFIGURATION/MEASUREMENTS
50h
AUTOCLASS CONTROL
R/W
1
0000,0000b
MAC4
51h
CHANNEL 1
AUTOCLASS PWR
MAC3
MAC2
MAC1
AAC4
AAC3
AAC2
AAC1
RO
1
0000,0000b
Rsrvd
Channel 1 AutoClass Power
52h
CHANNEL 2
AUTOCLASS PWR
RO
1
0000,0000b
Rsrvd
Channel 2 AutoClass Power
53h
CHANNEL 3
AUTOCLASS PWR
RO
1
0000,0000b
Rsrvd
Channel 3 AutoClass Power
54h
CHANNEL 4
AUTOCLASS PWR
RO
1
0000,0000b
Rsrvd
Channel 4 AutoClass Power
ALTERNATIVE
FOLDBACK
R/W
1
0000,0000b
ALTFB4
ALTFB3
ALTFB2
ALTFB1
ALTIR4
ALTIR3
ALTIR2
ALTIR1
RESERVED
R/W
1
0000,0000b
Rsrvd
Rsrvd
Rsrvd
Rsrvd
Rsrvd
Rsrvd
Rsrvd
Rsrvd
60h
SRAM CONTROL
R/W
1
0000,0000b
PROG_SEL
CPU_RST
Rsrvd
PAR_EN
61h
SRAM DATA
R/W
-
-
RAM_EN
PAR_SEL
RZ/W
CLR_PTR
R/W
1
0000,0000b
Programming Start Address (LSB)
R/W
1
0000,0000b
Programming Start Address (MSB)
R/W
1
0000,0000b
Rsrvd
Rsrvd
MISCELLANEOUS
55h
56h - 5Fh
SRAM
62h
START ADDRESS
63h
64h - 6Fh
38
RESERVED
SRAM DATA - Read and Write (continuous)
Rsrvd
Rsrvd
Rsrvd
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Rsrvd
Rsrvd
Rsrvd
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9.6.2 Detailed Register Descriptions
9.6.2.1 INTERRUPT Register
COMMAND = 00h with 1 Data Byte, Read only
Active high, each bit corresponds to a particular event that occurred. Each bit can be individually reset by doing a
read at the corresponding event register address, or by setting bit 7 of Reset register.
Any active bit of Interrupt register activates the INT output if its corresponding Mask bit in INTERRUPT Mask
register (01h) is set, as well as the INTEN bit in the General Mask register.
Figure 45. INTERRUPT Register Format
7
SUPF
R-1
6
STRTF
R-0
5
IFAULT
R-0
4
CLASC
R-0
3
DETC
R-0
2
DISF
R-0
1
PGC
R-0
0
PEC
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 5. INTERRUPT Register Field Descriptions
Bit
Field
Type
7
SUPF
R
Reset Description
1
Indicates that a Supply Event Fault or SRAM memory fault occurred
SUPF = TSD || VDUV || VDWRN || VPUV || RAMFLT
1 = At least one Supply Event Fault or SRAM memory fault occurred
0 = No such event occurred
6
STRTF
R
0
Indicates that a tSTART Fault occurred on at least one channel.
STRTF = STRT1 || STRT2 || STRT3 || STRT4
1 = tSTART Fault occurred for at least one channel
0 = No tSTART Fault occurred
5
IFAULT
R
0
Indicates that a tOVLD or tLIM Fault occurred on at least one channel.
IFAULT = PCUT1 || PCUT2 || PCUT3 || PCUT4 || PCUT34 || PCUT12 || ILIM1 || ILIM2 ||
ILIM3 || ILIM4
1 = tOVLD and/or tLIM Fault occurred for at least one channel
0 = No tOVLD nor tLIM Fault occurred
4
CLASC
R
0
Indicates that at least one classification cycle occurred on at least one channel
CLASC = CLSC1 || CLSC2 || CLSC3 || CLSC4
1 = At least one classification cycle occurred for at least one channel
0 = No classification cycle occurred
3
DETC
R
0
Indicates that at least one detection cycle occurred on at least one channel
DETC = DETC1 || DETC2 || DETC3 || DETC4
1 = At least one detection cycle occurred for at least one channel
0 = No detection cycle occurred
2
DISF
R
0
Indicates that a disconnect event occurred on at least one channel.
DISF = DISF1 || DISF2 || DISF3 || DISF4
1 = Disconnect event occurred for at least one channel
0 = No disconnect event occurred
1
PGC
R
0
Indicates that a power good status change occurred on at least one channel.
PGC = PGC1 || PGC2 || PGC3 || PGC4
1 = Power good status change occurred on at least one channel
0 = No power good status change occurred
0
PEC
R
0
Indicates that a power enable status change occurred on at least one channel
PEC = PEC1 || PEC2 || PEC3 || PEC4
1 = Power enable status change occurred on at least one channel
0 = No power enable status change occurred
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9.6.2.2 INTERRUPT MASK Register
COMMAND = 01h with 1 Data Byte, Read/Write
Each bit corresponds to a particular event or fault as defined in the Interrupt register.
Writing a 0 into a bit will mask the corresponding event/fault from activating the INT output.
Note that the bits of the Interrupt register always change state according to events or faults, regardless of the
state of the state of the Interrupt Mask register.
Note that the INTEN bit of the General Mask register must also be set in order to allow an event to activate the
INT output.
Figure 46. INTERRUPT MASK Register Format
7
SUMSK
R/W-1
6
STMSK
R/W-0
5
IFMSK
R/W-0
4
CLMSK
R/W-0
3
DEMSK
R/W-0
2
DIMSK
R/W-0
1
PGMSK
R/W-0
0
PEMSK
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 6. INTERRUPT MASK Register Field Descriptions
Bit
7
Field
Type
SUMSK
R/W
Reset Description
1
Supply Event Fault mask bit.
1 = Supply Event Fault will activate the INT output.
0 = Supply Event Fault will have no impact on INT output.
6
STMSK
R/W
0
tSTART Fault mask bit.
1 = tSTART Fault will activate the INT output.
0 = tSTART Fault will have no impact on INT output.
5
IFMSK
R/W
0
tOVLD or tLIM Fault mask bit.
1 = tOVLD and/or tLIM Fault occurrence will activate the INT output
0 = tOVLD and/or tLIM Fault occurrence will have no impact on INT output
4
CLMSK
R/W
0
Classification cycle mask bit.
1 = Classification cycle occurrence will activate the INT output.
0 = Classification cycle occurrence will have no impact on INT output.
3
DEMSK
R/W
0
Detection cycle mask bit.
1 = Detection cycle occurrence will activate the INT output.
0 = Detection cycle occurrence will have no impact on INT output.
2
DIMSK
R/W
0
Disconnect event mask bit.
1 = Disconnect event occurrence will activate th INT output.
0 = Disconnect event occurrence will have no impact on INT output.
1
PGMSK
R/W
0
Power good status change mask bit.
1 = Power good status change will activate the INT output.
0 = Power good status change will have no impact on INT output.
0
PEMSK
R/W
0
Power enable status change mask bit.
1 = Power enable status change will activate the INT output.
0 = Power enable status change will have no impact on INT output.
SPACE
NOTE
The contents of this register initializes to 0xE4 upon power up if the device is configured in
Autonomous mode with a valid RAUTO resistor connected to the AUTO pin.
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9.6.2.3 POWER EVENT Register
COMMAND = 02h with 1 Data Byte, Read only
COMMAND = 03h with 1 Data Byte, Clear on Read
Active high, each bit corresponds to a particular event that occurred.
Each bit xxx1-4 represents an individual channel.
A read at each location (02h or 03h) returns the same register data with the exception that the Clear on Read
command clears all bits of the register.
If this register is causing the INT pin to be activated, this Clear on Read will release the INT pin.
Any active bit will have an impact on the Interrupt register as indicated in the Interrupt register description.
Figure 47. POWER EVENT Register Format
7
PGC4
R-0
CR-0
6
PGC3
R-0
CR-0
5
PGC2
R-0
CR-0
4
PGC1
R-0
CR-0
3
PEC4
R-0
CR-0
2
PEC3
R-0
CR-0
1
PEC2
R-0
CR-0
0
PEC1
R-0
CR-0
LEGEND: R/W = Read/Write; R = Read only; ; CR = Clear on Read, -n = value after reset
Table 7. POWER EVENT Register Field Descriptions
Bit
Field
Type
7–4
PGC4–PGC1
R or
CR
Reset Description
0
R or
CR
0
Indicates that a power good status change occurred.
1 = Power good status change occurred
0 = No power good status change occurred
3–0
PEC4–PEC1
Indicates that a power enable status change occurred.
1 = Power enable status change occurred
0 = No power enable status change occurred
SPACE
NOTE
For 4-pair wired Ports, the PECn bits will be updated individually as status changes for
each channel.
For 4-Pair Single Signature devices, the PGCn bits will be set only after the status has
changed on both channels. This is done to prevent the possible scenario of dual interrupts
as the second Channel completes processing shortly after the first.
For 4-Pair Dual Signature devices, the PECn and PGCn bits will be set as the status
changes on each channel.
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9.6.2.4 DETECTION EVENT Register
COMMAND = 04h with 1 Data Byte, Read only
COMMAND = 05h with 1 Data Byte, Clear on Read
Active high, each bit corresponds to a particular event that occurred.
Each bit xxx1-4 represents an individual channel.
A read at each location (04h or 05h) returns the same register data with the exception that the Clear on Read
command clears all bits of the register. These bits are cleared when channel-n is turned off.
If this register is causing the INT pin to be activated, this Clear on Read will release the INT pin.
Any active bit will have an impact on the Interrupt register as indicated in the Interrupt register description.
Figure 48. DETECTION EVENT Register Format
7
CLSC4
R-0
CR-0
6
CLSC3
R-0
CR-0
5
CLSC2
R-0
CR-0
4
CLSC1
R-0
CR-0
3
DETC4
R-0
CR-0
2
DETC3
R-0
CR-0
1
DETC2
R-0
CR-0
0
DETC1
R-0
CR-0
LEGEND: R/W = Read/Write; R = Read only; ; CR = Clear on Read, -n = value after reset
Table 8. DETECTION EVENT Register Field Descriptions
Bit
Field
Type
7–4
CLSC4–CLSC1
R or
CR
Reset Description
0
Indicates that at least one classification cycle occurred if the CLCHE bit in General Mask
register is low. Conversely, it indicates when a change of class occurred if the CLCHE bit is
set.
1 = At least one classification cycle occurred (if CLCHE = 0) or a change of class
occurred (CLCHE = 1)
0 = No classification cycle occurred (if CLCHE = 0) or no change of class occurred
(CLCHE = 1)
3–0
DETC4–DETC1
R or
CR
0
Indicates that at least one detection cycle occurred if the DECHE bit in General Mask
register is low. Conversely, it indicates when a change in detection occurred if the DECHE
bit is set.
1 = At least one detection cycle occurred (if DECHE = 0) or a change in detection
occurred (DECHE = 1)
0 = No detection cycle occurred (if DECHE = 0) or no change in detection occurred
(DECHE = 1)
NOTE
For 4-Pair operated ports without a pending PWON command, these bits will be set only
after the status is ready for both channels. This is done to prevent the possible scenario
of dual interrupts as the second channel completes processing after the first.
The DETCn bits will only be set concurrently within 5ms of completing detection and
connection check on both channels
For a 4-pair single signature device, the CLSCn bit will only be set for the pair set
that classification was completed on even though the requested class will be given for
both channels in registers 0x0C-0F.
For a 4-pair dual signature device only doing discovery in Semi-auto mode, the
CLSCn bits will be set concurrently within 5ms of classification being completed on
both channels. In manual mode, the CLSCn bits will be set individually within 5ms of
classification being completed on each channels.
For 4-pair dual signature devices with a pending PWON command or in Auto mode,
the DETCn and CLSCn bits will be set independently as each channel completes its
portion of discovery during the dual-signature staggered turn on procedure.
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9.6.2.5 FAULT EVENT Register
COMMAND = 06h with 1 Data Byte, Read only
COMMAND = 07h with 1 Data Byte, Clear on Read
Active high, each bit corresponds to a particular event that occurred.
Each bit xxx1-4 represents an individual channel.
A read at each location (06h or 07h) returns the same register data with the exception that the Clear on Read
command clears all bits of the register. These bits are cleared when channel-n is turned off.
If this register is causing the INT pin to be activated, this Clear on Read will release the INT pin.
Any active bit will have an impact on the Interrupt register as indicated in the Interrupt register description.
Figure 49. FAULT EVENT Register Format
7
DISF4
R-0
CR-0
6
DISF3
R-0
CR-0
5
DISF2
R-0
CR-0
4
DISF1
R-0
CR-0
3
PCUT4
R-0
CR-0
2
PCUT3
R-0
CR-0
1
PCUT2
R-0
CR-0
0
PCUT1
R-0
CR-0
LEGEND: R/W = Read/Write; R = Read only; ; CR = Clear on Read, -n = value after reset
Table 9. FAULT EVENT Register Field Descriptions
Bit
Field
Type
7–4
DISF4–DISF1
R or
CR
Reset Description
0
R or
CR
0
Indicates that a disconnect event occurred.
1 = Disconnect event occurred
0 = No disconnect event occurred
3–0
PCUT4–PCUT1
Indicates that a tOVLD Fault occurred.
1 = tOVLD Fault occurred
0 = No tOVLD Fault occurred
SPACE
NOTE
For 4-pair wired ports, the DISFn and PCUTn bits will be updated individually as status
changes for each channel.
Disconnect events for 4-Pair single signature devices will set both corresponding bits,
whereas 4-pair dual signature devices will have independent disconnect events per
channel.
In the event a singular channel of a 4-pair dual signature device is turned off due to a
Disconnect or 2-Pair PCut fault, power may be reapplied to that channel by setting the
PWON bit in 0x19h provided the detection and classification are still valid and the Power
Allocation settings in 0x29 are sufficient based on the assigned classification of the
powered channel.
SPACE
If PCUT is disabled for a channel, this channel will not be automatically turned off during a PCUT fault condition.
However, the PCUT fault flag will still be operational, with a fault timeout equal to tOVLD.
Clearing a PCUT event has no impact on the TLIM or TOVLD counters.
SPACE
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9.6.2.6 START/ILIM EVENT Register
COMMAND = 08h with 1 Data Byte, Read only
COMMAND = 09h with 1 Data Byte, Clear on Read
Active high, each bit corresponds to a particular event that occurred.
Each bit xxx1-4 represents an individual channel.
A read at each location (08h or 09h) returns the same register data with the exception that the Clear on Read
command clears all bits of the register. These bits are cleared when channel-n is turned off.
If this register is causing the INT pin to be activated, this Clear on Read will release the INT pin.
Any active bit will have an impact on the Interrupt register as indicated in the Interrupt register description.
Figure 50. START/ILIM EVENT Register Format
7
ILIM4
R-0
CR-0
6
ILIM3
R-0
CR-0
5
ILIM2
R-0
CR-0
4
ILIM1
R-0
CR-0
3
STRT4
R-0
CR-0
2
STRT3
R-0
CR-0
1
STRT2
R-0
CR-0
0
STRT1
R-0
CR-0
LEGEND: R/W = Read/Write; R = Read only; ; CR = Clear on Read, -n = value after reset
Table 10. START/ILIM EVENT Register Field Descriptions
Bit
Field
Type
7–4
ILIM4–ILIM1
R or
CR
Reset Description
0
Indicates that a tLIM fault occurred, which means the channel has limited its output current
to ILIM or the folded back ILIM for more than tLIM.
1 = tLIM fault occurred
0 = No tLIM fault occurred
3–0
STRT4–STRT1
R or
CR
0
Indicates that a tSTART fault occurred during turn on.
1 = tSTART fault or class/detect error occurred
0 = No tSTART fault or class/detect error occurred
SPACE
NOTE
For 4-pair wired Ports:
The ILIMn bits will be updated individually as the status changes for each channel.
The STRTn bits will be updated individually as the status changes for each channel
When a Start Fault is reported and the PECn bit in Power Event register is set, then there
is an Inrush fault.
When a Start Fault is reported and the PECn bit is not set, then the Power-On Fault
register (0x24h) will indicate the cause of the fault.
In AUTO mode, STRTn faults will not be reported and register 0x24h will not be
updated due to invalid discovery results.
In the event a singular channel of a 4-pair dual signature PD is turned off due to a ILIM
fault or STRT fault, power may be reapplied to that channel by setting the PWON bit in
0x19h provided the detection and classification are still valid and the Power Allocation
settings in 0x29 are sufficient based on the assigned classification of the powered
channel.
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Inrush Fault (STRTn) Handling on 4-Pair wired ports:
For 4-pair wired ports with single signature PDs connected, the inrush behavior will vary based on assigned
classification given during turn on:
For 4P SS PD with an assigned classification of Class 6 or lower:
One channel will go through inrush while the second channel remains idle
If no STRT fault is detected at the end of inrush, the second channel will immediately turn on, and the
PGn bits will be set
If a STRT fault is detected at the end of inrush, the secondary channel will remain off and the primary
will be disabled, and a 1 sec cool-down period will be initiated on both channels. Both STRTn bits will be
set.
For 4P SS PD with an assigned classification of Class 7 or 8:
Both channels will go through inrush in parallel
If no STRT fault is detected at the end of inrush on either channel, the PGn bits will be set and the port
will remain powered.
If a STRT fault is detected at the end of inrush on either channel, both channels will be disabled, and a
1 sec cool-down period will be initiated on both channels. Both STRTn bits will be set.
For 4-pair wired ports with dual signature PDs connected, both channel will operate independent of the other.
Each will do perform inrush control during startup and if either channel faults, the remaining channel will be
unaffected.
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9.6.2.7 SUPPLY and FAULT EVENT Register
COMMAND = 0Ah with 1 Data Byte, Read only
COMMAND = 0Bh with 1 Data Byte, Clear on Read
Active high, each bit corresponds to a particular event that occurred.
A read at each location (0Ah or 0Bh) returns the same register data with the exception that the Clear on Read
command clears all bits of the register.
If this register is causing the INT pin to be activated, this Clear on Read will release the INT pin.
Any active bit will have an impact on the Interrupt register as indicated in the Interrupt register description.
Figure 51. SUPPLY and FAULT EVENT Register Format
7
TSD
R
CR
6
VDUV
R
CR
5
VDWRN
R
CR
4
VPUV
R
CR
3
PCUT34
R
CR
2
PCUT12
R
CR
1
OSSE
R
CR
0
RAMFLT
R
CR
LEGEND: R/W = Read/Write; R = Read only; ; CR = Clear on Read, -n = value after reset
Table 11. SUPPLY and FAULT EVENT Register Field Descriptions
Bit
7
Field
Type
TSD
R or
CR
POR/
RST
0/P
Description
Indicates that a thermal shutdown occurred. When there is thermal shutdown, all channels
are turned off and are put in OFF mode. The TPS23881 internal circuitry continues to
operate however, including the ADCs. Note that at as soon as the internal temperature has
decreased below the low threshold, the channels can be turned back ON regardless of the
status of the TSD bit.
1 = Thermal shutdown occurred
0 = No thermal shutdown occurred
6
VDUV
R or
CR
1/P
R or
CR
1/P
R or
CR
1/P
R or
CR
0/0
R or
CR
0/0
Indicates that a VDD UVLO occurred.
1 = VDD UVLO occurred
0 = No VDD UVLO occurred
5
VDWRN
Indicates that the VDD has fallen under the UVLO warning threshold.
1 = VDD UV Warning occurred
0 = No VDD UV warning occurred
4
VPUV
Indicates that a VPWR undervoltage occurred.
1 = VPWR undervoltage occurred
0 = No VPWR undervoltage occurred
3
PCUT34
Indicates that a 4-Pair Summed PCUT fault occurred on channels 3 and 4.
1 = 4-Pair Summed PCUT fault occurred on channels 3 and 4
0 = No Summed PCUT fault occurred
2
PCUT12
Indicates that a 4-Pair Summed PCUT fault occurred on channels 1 and 2.
1 = 4-Pair Summed PCUT fault occurred on channels 1 and 2
0 = No Summed PCUT fault occurred
1
OSSE
R or
CR
0/0
Indicates that an OSS Event occurred
1 = one or more channels with a group of 4 were disabled due to the assertion of the
OSS pin or provided 3-bit OSS code
0 = No OSS events occurred
0
RAMFLT
R or
CR
0/0
Indicates that a SRAM fault has occurred
1 = SRAM fault occurred
0 = No SRAM fault occurred
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SPACE
NOTE
The RST condition of "P" indicates that the previous state of these bits will be preserved
following a device reset using the RESET pin. Thus, pulling the RESET input low will not
clear the TSD, VDUV, VDWRN, or VPUV bits.
NOTE
While the VPUV bit is set, any PWONn commands will be ignored until VVPWR > 30 V.
During VPUV undervoltage condition, the Detection Event register (CLSCn, DETCn) is not
cleared, unless VPWR also falls below the VPWR UVLO falling threshold
(approximately18 V).
A clear on Read will not effectively clear VDUV bit as long as the VPWR undervoltage
condition is maintained.
NOTE
In 1-bit mode (MbitPrty = 0 in reg 0x17), the OSSE bit will be set anytime a channel within
a group of 4 has OSS enabled and the OSS pin is asserted.
In 3-bit mode (MbitPrty = 1 in reg 0x17), the OSSE bit will be set anytime a 3-bit priority
code is sent that is equal to or greater than the MBPn settings in registers 0x27 and 0x28
channel for a group of 4 channels.
SPACE
For a 4-pair wired port, if 4P PCUT is disabled (4PPCTxx = 0 in 0x2D), the port will not be automatically turned
off during a 4P-PCUT fault condition. However, the PCUTnn fault bits will still be operational, with a fault timeout
equal to tOVLD. Also, if a Clear on Read is done at the Fault Event register, the PCUTnn bit is reset, and the
associated summed PCUT counter is reset. Only the Channels reporting such interrupt have their counter
cleared by the CoR operation. Also, clearing a PCUT fault has no impact on TLIM counter.
SPACE
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9.6.2.7.1 Detected SRAM Faults and "Safe Mode"
The TPS23881 is configured with internal SRAM memory fault monitoring, and in the event that an error is
detected with the SRAM memory, the device will enter “safe mode”. While in “Safe mode” the FW Revision value
in register 0x41 will be set to 0xFFh.
Any channels that are currently powered will remain powered, but the majority of the operation will be disabled
until the SRAM can be reloaded. The device UVLO and Thermal Shutdown features in addition to the disconnect
and current foldback functions for the powered channels will be preserved in “safe mode”.
Any channels that were not powered prior to the SRAM fault detection will be set to OFF mode (see register
0x12h description for additional changes that will occur as a result of the change to OFF mode). Port Remapping
(0x26h) and any other channel configuration settings (ie Power Allocation 0x29h) will be preserved.
Upon detection of a SRAM fault the “RAM_EN” bit in 0x60 will be cleared and the RAMFLT bit will be set in
register 0x0A. The internal firmware will continue to run in “safe mode” until this bit is set again by the host after
the SRAM is reloaded or a POR (Power on Reset) event occurs. In order to ensure a smooth transition into and
out of “safe mode”, any I2C commands other than those to reprogram the SRAM need to be deferred until after
the SRAM is reloaded and determined to be “valid” (see register 0x60 SRAM programing descriptions).
NOTE
Once set, the RAMFLT bit will remain set even after the device is removed from safe
mode. it is recommend that this bit be cleared prior to setting the RAM_EN bit in register
0x60 following the SRAM reload.
NOTE
The PAR_EN bit in reg 0x60 must be set and the corresponding SRAM_Parity code
(available for download from the TI mySecure Software webpage) must be loaded into the
device in order for the SRAM fault monitoring to be active.
Please refer to the How to Load TPS2388x SRAM Code document for more information
on the recommended SRAM programming procedure.
SPACE
9.6.2.7.1.1 ULA (Ultra Low Alpha) Package Option: TPS23881A
Over time, SRAM faults may occur due to alpha-induced 'soft-errors' from the naturally occurring Alpha particles
in the atmosphere or semiconductor packaging itself. If enough of these Alpha particles are collected in the
memory structure of the silicon, the cumulative electrical charge of these particles can flip the state of one or
more logic gates.
To minimize the potential for these alpha-induced SRAM faults, users can choose to use the TPS23881A
package option which has a specialized ULA (Ultra Low Alpha) packaging mold compound that reduces the
silicon's exposure to Alpha particles by a factor of roughly 10x.
48
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9.6.2.8 CHANNEL 1 DISCOVERY Register
COMMAND = 0Ch with 1 Data Byte, Read Only
Figure 52. CHANNEL 1 DISCOVERY Register Format
7
R-0
6
5
REQUESTED CLASS Ch1
R-0
R-0
4
3
2
1
0
R-0
R-0
1
0
R-0
R-0
1
0
R-0
R-0
1
0
R-0
R-0
DETECT Ch1
R-0
R-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.9 CHANNEL 2 DISCOVERY Register
COMMAND = 0Dh with 1 Data Byte, Read Only
Figure 53. CHANNEL 2 DISCOVERY Register Format
7
R-0
6
5
REQUESTED CLASS Ch2
R-0
R-0
4
3
2
DETECT Ch2
R-0
R-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.10 CHANNEL 3 DISCOVERY Register
COMMAND = 0Eh with 1 Data Byte, Read Only
Figure 54. CHANNEL 3 DISCOVERY Register Format
7
R-0
6
5
REQUESTED CLASS Ch3
R-0
R-0
4
3
2
DETECT Ch3
R-0
R-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.11 CHANNEL 4 DISCOVERY Register
COMMAND = 0Fh with 1 Data Byte, Read Only
Figure 55. CHANNEL 4 DISCOVERY Register Format
7
R-0
6
5
REQUESTED CLASS Ch4
R-0
R-0
4
3
2
DETECT Ch4
R-0
R-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Bit Descriptions: These bits represent the most recent "requested" classification and detection results for
channel n. These bits are cleared when channel n is turned off.
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Table 12. CHANNEL n DISCOVERY Register Field Descriptions
Bit Field
7–4 RCLASS
Ch-n
Type Reset
R
0
Description
Most recent classification result on channel n.
The selection is as following:
RCLASS Ch-n
3–0 DETECT
Ch-n
R
0
Requested Class
0
0
0
0
Unknown
0
0
0
1
Class 1
0
0
1
0
Class 2
0
0
1
1
Class 3
0
1
0
0
Class 4
0
1
0
1
Reserved – read as Class 0
0
1
1
0
Class 0
0
1
1
1
Class Overcurrent
1
0
0
0
Class 5 - 4-Pair Single Signature
1
0
0
1
Class 6 - 4-Pair Single Signature
1
0
1
0
Class 7 - 4-Pair Single Signature
1
0
1
1
Class 8 - 4-Pair Single Signature
1
1
0
0
Class 4+ - Type-1 Limited
1
1
0
1
Class 5 - 4-Pair Dual Signature
1
1
1
0
Reserved
1
1
1
1
Class Mismatch
Most recent detection result on channel n.
The selection is as following:
DETECT Ch-n
50
Detection Status
0
0
0
0
Unknown
0
0
0
1
Short-circuit
0
0
1
0
Reserved
0
0
1
1
Too Low
0
1
0
0
Valid
0
1
0
1
Too High
0
1
1
0
Open Circuit
0
1
1
1
Reserved
1
1
1
0
MOSFET fault
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“Requested” vs. “Assigned” Classification: The “requested” class is the classification the PSE measures during
Mutual Identification prior to turn on, whereas the “assigned” class is the classification level the channel was
powered on with based on the Power Allocation setting in register 0x29h. The “assigned” classification values are
available in registers 0x4C-4F
NOTE
Due to the need to power on after 1 class finger, the "Class 4+ - Type 1 Limited"
Requested Class is reported anytime a Class 4 or higher PD is powered with register 0x29
configured for 15.5W.
For a 4-pair single signature device, both channels will report the requested PD
classification within 5ms after classification is completed. However, only the channel that
classification was measured on will have the CLSCn bit set in register 0x04h
For a 4-pair dual signature device each channel will reports is own individually requested
PD classification within 5ms after classification is completed on each Channel
Upon being powered, devices that present a class 0 signature during discovery will be
given an assigned class of "Class 3"
In Manual/Diagnostic mode, Class 8 4-pair single signature loads will be reported as
"Class 5DS" when classification is only enabled on one channel.
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9.6.2.12 POWER STATUS Register
COMMAND = 10h with 1 Data Byte, Read only
Each bit represents the actual power status of a channel.
Each bit xx1-4 represents an individual channel.
These bits are cleared when channel-n is turned off, including if the turn off is caused by a fault condition.
Figure 56. POWER STATUS Register Format
7
PG4
R-0
6
PG3
R-0
5
PG2
R-0
4
PG1
R-0
3
PE4
R-0
2
PE3
R-0
1
PE2
R-0
0
PE1
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 13. POWER STATUS Register Field Descriptions
Bit
Field
7–4
PG4–PG1
Type
Reset Description
R
0
Each bit, when at 1, indicates that the channel is on and that the voltage at DRAINn pin has
gone below the power good threshold during turn on.
These bits are latched high once the turn on is complete and can only be cleared when the
channel is turned off or at RESET/POR.
1 = Power is good
0 = Power is not good
3–0
PE4–PE1
R
0
Each bit indicates the ON/OFF state of the corresponding channel.
1 = Channel is on
0 = Channel is off
For 4-pair wired ports, these bits will be updated individually as the status changes for each channel
For 4-Pair Single Signature devices, the PGn bits will be set only after the status has changed on both channels.
This is done to prevent the possible scenario of dual interrupts as the second channel completes processing after
the first.
For 4-Pair Dual Signature devices, the PECn and PGCn bits will be set as the status changes on each channel.
52
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9.6.2.13 PIN STATUS Register
COMMAND = 11h with 1 Data Byte, Read Only
Figure 57. PIN STATUS Register Format
7
AUTO
AUTO pin
6
SLA4
A4 pin
5
SLA3
A3 pin
4
SLA2
A2 pin
3
SLA1
A1 pin
2
SLA0
0/1 (1)
1
0
0
0
0
0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
(1)
If Configuration A, it can be 0 or 1. If configuration B, it is 0.
Table 14. PIN STATUS Register Field Descriptions
Bit
Field
Type
7
AUTO
R
Reset Description
AUTO Autonomous mode enabled bit.
0 = Autonomous mode disabled (AUTO pin floating)
1 = Autonomous mode enabled (Valid resistance confected between Auto pin and GND)
Note: This bit will only be set in the lower I2C register set (channel 1-4).
6-3
2
SLA4-SLA1
R
SLA0
R
See I2C device address, as defined while using pins A4-A1.
above
SLA0 bit is internally defined to 0 or 1
0 = Channel 1-4
1 = Channels 5-8
DESCRIPTION
BINARY DEVICE ADDRESS
ADDRESS PINS
6
5
4
3
2
1
0
A4
A3
A2
A1
Broadcast access
1
1
1
1
1
1
1
X
X
X
X
Slave 0
0
1
0
0
0
0
0/1
GND
GND
GND
GND
0
1
0
0
0
1
0/1
GND
GND
GND
HIGH
0
1
0
0
1
0
0/1
GND
GND
HIGH
GND
0
1
0
0
1
1
0/1
GND
GND
HIGH
HIGH
0
1
0
1
0
0
0/1
GND
HIGH
GND
GND
0
1
0
1
0
1
0/1
GND
HIGH
GND
HIGH
0
1
0
1
1
0
0/1
GND
HIGH
HIGH
GND
0
1
0
1
1
1
0/1
GND
HIGH
HIGH
HIGH
0
1
1
0
0
0
0/1
HIGH
GND
GND
GND
0
1
1
0
0
1
0/1
HIGH
GND
GND
HIGH
0
1
1
0
1
0
0/1
HIGH
GND
HIGH
GND
0
1
1
0
1
1
0/1
HIGH
GND
HIGH
HIGH
0
1
1
1
0
0
0/1
HIGH
HIGH
GND
GND
0
1
1
1
0
1
0/1
HIGH
HIGH
GND
HIGH
0
1
1
1
1
0
0/1
HIGH
HIGH
HIGH
GND
0
1
1
1
1
1
0/1
HIGH
HIGH
HIGH
HIGH
Slave 15
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9.6.2.13.1 AUTONOMOUS MODE
In autonomous mode, the TPS23881 is capable of operating without any I2C communication or host control. As
in auto mode, when the device is operating in autonomous mode, the ports will be continuously cycling through
discovery, and the ports will automatically power whenever a valid (defection and classification) PD is connected.
Connecting a resistor between the AUTO pin and GND based on the table below will enable autonomous mode
and configure all the ports to the same Power Allocation settings. In the event a PD is connected with a higher
requested class than the autonomous mode configuration, the port will power demote the PD to the selected
autonomous mode configuration power level.
Table 15. AUTO Pin Programming
Auto Pin
Autonomous Mode Configuration
Resulting Register Configurations
0x12h
0x14h
0x29h
Open/Floating
Disabled
0000, 0000b
0000, 0000b
0000, 0000b
124 kΩ
2-pair 15W
1111, 1111b
1111, 1111b
0000, 0000b
0011 0011b
62 kΩ
2-pair 30W
1111, 1111b
1111, 1111b
35.7 kΩ
4-pair 30W
1111, 1111b
1111, 1111b
1011 1011b
22.6 kΩ
4-pair 45W
1111, 1111b
1111, 1111b
1100, 1100b
15.8 kΩ
4-pair 60W
1111, 1111b
1111, 1111b
1101, 1101b
11 kΩ
4-pair 75W
1111, 1111b
1111, 1111b
1110, 1110b
7.7 kΩ
4-pair 90W
1111, 1111b
1111, 1111b
1111, 1111b
SPACE
NOTE
A 10 nF capacitor is required in parallel with RAUTO to ensure stability in the Autonomous
mode selection.
The I2C interface is still fully operational in Autonomous mode, and the all of the port
telemetry and configurability is still supported
The Auto pin resistance (RAUTO) will not be measured following a device reset (assertion
of the RESET pin or RESAL bit in register 0x1A). The device wil only measured (RAUTO)
and pre-configure the internal registers during power up (VVPWR and VVDD rising above
their respective UVLO thresholds).
NOTE
The device SRAM will need to be programmed in order to support applications that desire
to remove a device from Autonomous mode after having initially powered up in
Autonomous mode.
A device running from the internal ROM (SRAM unprogrammed) in Autonomous mode will
turn off and automatically resume discovery and power on any valid loads following the
assertion of the RESET pin, I2C register 0x1A RESAL or RESPn bits, or a mode off
command. Whereas a device running in Autonomous mode with the SRAM programmed
will turn off and remain inactive until the host re-enables the port(s) through the I2C bus.
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9.6.2.14 OPERATING MODE Register
COMMAND = 12h with 1 Data Byte, Read/Write
Figure 58. OPERATING MODE Register Format
7
C4M1
R/W-0
6
C4M0
R/W-0
5
C3M1
R/W-0
4
C3M0
R/W-0
3
C2M1
R/W-0
2
C2M0
R/W-0
1
C1M1
R/W-0
0
C1M0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 16. OPERATING MODE Register Field Descriptions
Bit
Field
Type
Reset
7-0
CnM1–CnM0
R/W
0
Description
Each pair of bits configures the operating mode per channel.
The selection is as following:
M1
M0
Operating Mode
0
0
OFF
0
1
Diagnostic/Manual
1
0
Semiauto
1
1
Auto
For a 4-pair wired port, both channels must be set to the same operating mode. Otherwise,
the port will not conduct discovery, and any turn on commands will be ignored.
SPACE
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OFF MODE:
In OFF mode, the Channel is OFF and neither detection nor classification is performed independent of the DETE,
CLSE or PWON bits.
The table below depicts what bits will be cleared when a channel is changed to OFF mode from any other
operating mode:
Table 17. Transition to OFF Mode
Register
Bits to be reset
0x04
CLSCn and DETCn
0x06
DISFn and PCUTn
0x08
STRTn and ILIMn
0x0A/B
0x0C-0F
PCUTnn
Requested Class and Detection
0x10
PGn and PEn
0x14
CLEn and DETEn
0x1C
ACn and CCnn
0x1E-21
0x24
0x2A-2B
0x2D
0x30-3F
0x40
2P Policing set to 0xFFh
PFn
4P Policing set to 0xFFh
NLMnn, NCTnn, 4PPCTnn, and DCDTnn
Channel Voltage and Current Measurements
2xFBn
0x44 - 47
Detection Resistance Measurements
0x4C-4F
Assigned Class and Previous Class
0x51-54
Autoclass Measurement
SPACE
NOTE
it may take upwards of 5 ms before all of the registers are cleared following a change to
OFF mode.
Only the bits associated with the channel/port ("n") being set into OFF mode will be cleared. Those bits
associated with channels/ports remaining in operation will not be changed.
In the event either the PGn or PEn bits were changed from a 1 to a zero, the corresponding PGCn and PECn
bits will be set in the POWER EVENT register 0x02h.
Also, a change of mode from semiauto to manual/diagnostic mode or OFF mode will cancel any ongoing
cooldown time period.
SPACE
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DIAGNOSTIC/MANUAL MODE:
In Manual/Diagnostic mode, there is no automatic state change. The channel remains idle until DETE, CLSE
(0x14h or 0x18h), or PWON command is provided. Upon the setting of the DETE and/or CLSE bits, the channel
will perform a singular detection and/or classification cycle on the corresponding channel.
SPACE
NOTE
Setting a PWONn bit in register 0x19 results in the immediate turn on of that channel.
There is no Assigned Class assigned for ports/channels powered out of Manual/Diagnostic
mode. Any settings such as the port power policing and 1x/2x foldback selection that are
typically configure based on the assigned class result need to manually configured by the
user.
For 4-Pair wired ports (4PWnn bit in 0x29 = 1):
Setting the DETE or CLSE bits on only one channel will result in detection and/or classification only being
done on that channel, and Connection Check will not be preformed.
Setting the DETE bits for both channels during the same I2C operation will result in detection cycles being
completed on both channels, and if the detection results are valid, connection check will also be completed.
Setting the CLSE bits for both channels during the same I2C operation will result in staggered classification
measurements being done on both channels
NOTE
Setting a PWONn bit in register 0x19 results in the immediate turn on of that channel.
NOTE
DC Disconnect for 4-Pair ports power on in Manual/Diagnostic mode will behave as
independent channels. Thus, if either channel current falls below VIMIN for longer than
tMPDO , that channel will be disabled and a disconnect fault will be set (DISFn bits in
register 0x06/7).
Table 18. Channel Behavior in Diagnostic/Manual Mode
CLEn
DETn
PWONn
Channel Operation
0
0
0
Idle
0
1
0
Single Detection measurement (Connection check completed if 4P wired and
DETE bits are set for both channels)
1
0
0
Single Classification measurement
1
1
0
Single Detection and Classification measurement done. (Connection check
completed if 4P wired and both DETE and CLE bits are set for both channels)
-
-
1
Channel immediate turns on without any detection or classification being
performed
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SEMI AUTO MODE:
In Semi Auto mode, as long as the Channel is unpowered, detection and classifications may be performed
continuously depending if the corresponding class and detect enable bits are set (register 0x14h).
Table 19. Channel Behavior in Semi Auto Mode
CLEn
DETn
0
0
Channel Operation
Idle
0
1
Cycling Detection Measurements only
1
0
Idle
1
1
Cycling Detection and Classification Measurements
NOTE
If two channels are configured as a 4-pair wired port, a connection check measurement
will be performed once a valid detection result is seen on one of the channel
For a 4-Pair Dual Signature PD that has only one channel powered, the unpowered channel will resume detect
and class provided the DETE and CLE bits are set for that channel in 0x14h.
SPACE
AUTO MODE:
In Auto mode, channels will automatically power on any valid detection and classification signature based on the
Port Power Allocation settings in 0x29. The channels will remain idle until DETE and CLSE (0x14 or 0x18) are
set, or a PWON command is given.
Prior to setting DETE and CLE or sending a PWON command in AUTO mode, the following registers need to be
configured according to the system requirements and configuration:
Register
Bits
0x26
Port Re-mapping
0x29
4-Pair Wired and Port Power Allocation
0x50
Auto AC Enable
0x55
Alternative Inrush and Powered Foldback Enable
NOTE
Changes to these registers after the DETE and CLE bits are set in Auto mode may result
in undesired or non IEEE complaint operation.
The following registers may be configured or changed after turn on if changes to the default operation are
desired as these values are internally set during power on based on the port configuration and resulting assigned
PD class:
58
Register
Bits
0x1E-21
2-Pair Policing
0x2A-2B
4-Pair Policing
0x2D
4P Pcut Enable and DC Disconnect Threshold bits
0x40
2x Foldback Enable
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9.6.2.15 DISCONNECT ENABLE Register
COMMAND = 13h with 1 Data Byte, Read/Write
Bit Descriptions: Defines the disconnect detection mechanism for each channel.
Figure 59. DISCONNECT ENABLE Register Format
7
–
R/W-0
6
–
R/W-0
5
–
R/W-0
4
–
R/W-0
3
DCDE4
R/W-1
2
DCDE3
R/W-1
1
DCDE2
R/W-1
0
DCDE1
R/W-1
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 20. DISCONNECT ENABLE Register Field Descriptions
Bit
Field
Type
7–4
—
R/W
Reset Description
0
3–0
DCDE4–DCDE1
R/W
1
DC disconnect enable
1 = DC Disconnect Enabled
0 = DC Disconnect Disabled
Look at the TIMING CONFIGURATION register for more details on how to define the TDIS
time period.
DC disconnect consists in measuring the Channel DC current at SENn, starting a timer (TDIS) if this current is
below a threshold and turning the Channel off if a time-out occurs. Also, the corresponding disconnect bit
(DISFn) in the FAULT EVENT register is set accordingly. The TDIS counter is reset each time the current rises
above the disconnect threshold for at least 3 msec. The counter does not decrement below zero.
NOTE
For 4P Single signature devices, if either DCDEx bit is set, both channels will be shut off
when the disconnect timer expires.
In the event a singular channel of a 4-pair dual signature PD is turned off due to a
disconnect fault or other reason, power may be reapplied to that channel by setting the
PWON bit in 0x19h provided the detection and classification are still valid and the Power
Allocation settings in 0x29 are sufficient based on the assigned classification of the
powered channel.
NOTE
The DCDTnn bits in 0x2D set the disconnect threshold.
The DCDTnn bits are automatically configured during turn on based on the 4PWnn bits in
0x29 and the Assigned classification results (0x4C-4F) based on IEEE compliance
requirements.
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9.6.2.16 DETECT/CLASS ENABLE Register
COMMAND = 14h with 1 Data Byte, Read/Write
During tOVLD, tLIM or tSTART cool down cycle, any Detect/Class Enable command for that channel will be delayed
until end of cool-down period. Note that at the end of cool down cycle, one or more detection/class cycles are
automatically restarted as described previously, if the class and/or detect enable bits are set.
Figure 60. DETECT/CLASS ENABLE Register Format
7
CLE4
R/W-0
6
CLE3
R/W-0
5
CLE2
R/W-0
4
CLE1
R/W-0
3
DETE4
R/W-0
2
DETE3
R/W-0
1
DETE2
R/W-0
0
DETE1
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 21. DETECT/CLASS ENABLE Register Field Descriptions
Bit
Field
Type
Reset Description
7–4
CLE4-CLE1
R/W
0
Classification enable bits.
3–0
DETE4-DETE1
R/W
0
Detection enable bits.
Bit Descriptions:
Detection and classification enable for each channel.
When in Manual mode, setting a bit means that only one cycle (detection or classification) is performed for
the corresponding channel. The bit is automatically cleared by the time the cycle has been completed.
Note that similar result can be obtained by writing to the Detect/Class Restart register 0x18.
It is also cleared if a turn off (Power Enable register) command is issued.
When in semiauto mode, as long as the port is kept off, detection and classification are performed
continuously, as long as the class and detect enable bits are kept set, but the class will be done only if the
detection was valid. A Detect/Class Restart PB command can also be used to set the CLEn and DETEn bits,
if in semiauto mode.
NOTE
For 4-pair wired Ports in Semi-Auto or Auto mode, both DETEn and CLEn bits need to be
set on both channels in order for Detection or Classification to be enabled
NOTE
In Manual/Diagnostic mode, it is recommenced that a Port Reset command (see register
0x1A RESET Register) be completed prior to enabling discovery (DETEn or CLEn).
60
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9.6.2.17 Power Priority / 2Pair PCUT Disable Register Name
COMMAND = 15h with 1 Data Byte, R/W
Figure 61. Power Priority / 2P-PCUT Disable Register Format
7
OSS4
R/W-0
6
OSS3
R/W-0
5
OSS2
R/W-0
4
OSS1
R/W-0
3
DCUT4
R/W-0
2
DCUT3
R/W-0
1
DCUT2
R/W-0
0
DCUT1
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 22. Power Priority / 2P-PCUT Disable Register Field Descriptions
Bit
Field
Type
Reset
7–4
OSS4-OSS1
R/W
0
Description
Power priority bits:
When the MBitPrty bit in 0x17 =0:
1 = When the OSS signal is asserted, the corresponding channel is powered off.
0 = OSS signal has no impact on the channel.
For 4-pair wired Ports, these bits control the individual Channel response. In order for
both channels of a 4-pair wired port to be disabled, both channels need to be set to 1.
3–0
DCUT4-DCUT1
R/W
0
2-Pair PCUT disable for each channel. Used to prevent removal of the associated
channel’s power due to a 2-Pair PCUT fault, regardless of the programming status of the
Timing Configuration register. Note that there is still monitoring of ILIM faults.
1: Channel’s PCUT is disabled. This means that an PCUT fault alone will not turn off
this channel.
0: Channel’s PCUT is enabled. This enables channel turn off if there is PCUT fault.
SPACE
NOTE
If the MbitPrty bit = 1 (0x17h): The OSSn bits must be cleared to ensure proper operation.
Refer to registers 0x27/28h for more information on the Multi-bit priority shutdown feature.
NOTE
If DCUT = 1 for a channel, the channel will not be automatically turned off during a PCUT
fault condition. However, the PCUT fault flag will still be operational, with a fault timeout
equal to tOVLD.
Any change in the state of DCUTn bits will result in the resetting of the TOVLD timer for that
channel.
NOTE
For 4-pair wired Ports:
These bits control the individual Channel response to a 2-Pair PCUT fault.
If the NCTnn bit in 0x2D = 1 and the 2-Pair PCut is enabled, both channel will be
turned off if the overload condition exceeds the tOVLD timeout.
The response to a summed 4-pair PCUT fault is configured in register 0x2Dh.
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The OSSn bits are used to determine which channels are shut down in response to an external assertion of the
OSS fast shutdown signal.
The turn off procedure due to OSS is similar to a channel reset or change to OFF mode, with the exception that
OSS does not cancel any ongoing fault cool down timers. the table below includes the bits that will be cleared
when a channel is disabled due to OSS:
Table 23. Channel Turn Off with OSS
Register
Bits to be reset
0x04
CLSCn and DETCn
0x06
DISFn and PCUTn
0x08
STRTn and ILIMn
0x0A/B
0x0C-0F
PCUTnn
Requested Class and Detection
0x10
PGn and PEn
0x14
CLEn and DETEn
0x1C
ACn and CCnn
0x1E-21
0x24
0x2A-2B
0x2D
0x30-3F
0x40
2P Policing set to 0xFFh
PFn
4P Policing set to 0xFFh
NLMnn, NCTnn, 4PPCTnn, and DCDTnn
Channel Voltage and Current Measurements
2xFBn
0x44 - 47
Detection Resistance Measurements
0x4C-4F
Assigned Class and Previous Class
0x51-54
Autoclass Measurement
SPACE
NOTE
it may take upwards of 5 ms before all of the registers are cleared following an OSS
event.
Only the bits associated with the channel/port ("n") with OSS enabled will be cleared. Those bits associated with
channels/ports remaining in operation will not be changed.
In the event a singular channel of a 4-pair dual signature PD is turned off due to OSS or PCUT fault, power may
be reapplied to that channel by setting the PWON bit in 0x19h provided the detection and classification are still
valid and the Power Allocation settings in 0x29 are sufficient based on the assigned classification of the powered
channel.
62
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9.6.2.18 TIMING CONFIGURATION Register
COMMAND = 16h with 1 Data Byte, Read/Write
Bit Descriptions: These bits define the timing configuration for all four channels.
Figure 62. TIMING CONFIGURATION Register Format
7
6
5
4
TLIM
R/W-0
3
TSTART
R/W-0
R/W-0
2
1
TOVLD
R/W-0
R/W-0
0
TMPDO
R/W-0
R/W-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 24. TIMING CONFIGURATION Register Field Descriptions
Bit
Field
Type
Reset
7 –6
TLIM
R/W
0
Description
ILIM fault timing, which is the output current limit time duration before channel turn off.
When a 2xFBn bit in register 0x40 = 0, the tLIM used for the associated channel is always the
nominal value (about 60 ms).
This timer is active and increments to the settings defined below after expiration of the TSTART time
window and when the channel is limiting its output current to ILIM. If the ILIM counter is allowed to
reach the programmed time-out duration specified below, the channel will be powered off. The 1second cool down timer is then started, and the channel can not be turned-on until the counter has
reached completion.
In other circumstances (ILIM time-out has not been reached), while the channel current is below ILIM,
the same counter decrements at a rate 1/16th of the increment rate. The counter does not
decrement below zero. The ILIM counter is also cleared in the event of a turn off due to a Power
Enable or Reset command, a DC disconnect event or the OSS input.
Note that in the event the TLIM setting is changed while this timer is already active for a channel,
this timer is automatically reset then restarted with the new programmed time-out duration.
Note that at the end of cool down cycle, when in semiauto mode, a detection cycle is automatically
restarted if the detect enable bit is set. Also note that the cool down time count is immediately
canceled with a reset command, or if the OFF or Manual mode is selected.
If 2xFBn bit is asserted in register 0x40, then tLIM for associated channel is programmable with the
following selection:
TLIM
5-4
TSTART
(or
TINRUSH)
R/W
0
Minimum tLIM (ms)
0
0
58
0
1
15
1
0
10
1
1
6
START fault timing, which is the maximum allowed overcurrent time during inrush. If at the end of
TSTART period the current is still limited to IInrush, the channel is powered off.
This is followed by a 1-second cool down period, during which the channel can not be turned-on
Note that at the end of cool down cycle, when in semiauto mode, a detection cycle is automatically
restarted if the class and detect enable bits are set.
Note that in the event the TSTART setting is changed while this timer is already active for a channel,
this new setting is ignored and will be applied only next time the channel is turned ON.
The selection is as following:
TSTART
Nominal tSTART (ms)
0
0
60
0
1
30
1
0
120
1
1
Reserved
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Table 24. TIMING CONFIGURATION Register Field Descriptions (continued)
Bit
Field
Type
Reset
Description
3–2
TOVLD
R/W
0
PCUT fault timing, which is the overcurrent time duration before turn off. This timer is active and
increments to the settings defined below after expiration of the TSTART time window and when the
current meets or exceeds PCUT, or when it is limited by the current foldback. If the PCUT counter is
allowed to reach the programmed time-out duration specified below, the channel will be powered off.
The 1-second cool down timer is then started, and the channel can not be turned-on until the
counter has reached completion.
In other circumstances (PCUT time-out has not been reached), while the current is below PCUT, the
same counter decrements at a rate 1/16th of the increment rate. The counter does not decrement
below zero. The PCUT counter is also cleared in the event of a turn off due to a Power Enable or
Reset command, a DC disconnect event or the OSS input
Note that in the event the TOVLD setting is changed while this timer is already active for a channel,
this timer is automatically reset then restarted with the new programmed time-out duration.
Note that at the end of cool down cycle, when in semiauto mode, a detection cycle is automatically
restarted if the detect enable bit is set. Also note that the cool down time count is immediately
canceled with a reset command, or if the OFF or Manual mode is selected.
Note that if a DCUTn bit is high in the Power Priority/PCUT Disable register, the PCUT fault timing
for the associated channel is still active. However, even though the channel will not be turned off
when the tOVLD time expires, the PCUT fault bits will still be set.
The selection is as following:
1–0
TMPDO
R/W
0
TOVLD
Nominal tOVLD (ms)
0
0
60
0
1
30
1
0
120
1
1
240
Disconnect delay, which is the time to turn off a channel once there is a disconnect condition, and if
the dc disconnect detect method has been enabled.
The TDIS counter is reset each time the current goes continuously higher than the disconnect
threshold for nominally 15 ms.
The counter does not decrement below zero.
The selection is as following:
TMPDO
Nominal tMPDO (ms)
0
0
360
0
1
90
1
0
180
1
1
720
SPACE
NOTE
The PGn and PEn bits (Power Status register) are cleared when there is a TLIM, TOVLD,
TMPDO, or TSTART fault condition.
NOTE
The settings for tLIM set the minimum timeout based on the IEEE compliance
requirements.
NOTE
The tOVLD time for 4-pair Pcut faults will be equal to the tOVLD setting + approximately 6 ms
64
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9.6.2.19 GENERAL MASK Register
COMMAND = 17h with 1 Data Byte, Read/Write
Figure 63. GENERAL MASK Register Format
7
INTEN
R/W-1
6
–
R/W-0
5
nbitACC
R/W-0
4
MbitPrty
R/W-0
3
CLCHE
R/W-0
2
DECHE
R/W-0
1
–
R/W-0
0
–
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 25. GENERAL MASK Register Field Descriptions
Bit
7
Field
Type
INTEN
R/W
Reset Description
1
INT pin mask bit. Writing a 0 will mask any bit of Interrupt register from activating the INT
output, whatever the state of the Interrupt Mask register. Note that activating INTEN has no
impact on the event registers.
1 = Any unmasked bit of Interrupt register can activate the INT output
0 = INT output cannot be activated
6
–
R/W
0
5
nbitACC
R/W
0
I2C Register Access Configuration bit.
1 = Configuration B. This means 16-bit access with a single device address (A0 = 0).
0 = Configuration A. This means 8-bit access, while the 8-channel device is treated as
2 separate 4-channel devices with 2 consecutive slave addresses.
See register 0x11 for more information on the I2C address programming
4
MbitPrty
R/W
0
Multi Bit Priority bit. Used to select between 1-bit shutdown priority and 3-bit shutdown
priority.
1 = 3-bit shutdown priority. Register 0x27 and 0x28 need to be followed for priority and
OSS action.
0 = 1-bit shutdown priority. Register 0x15 needs to be followed for priority and OSS
action
3
CLCHE
R/W
0
Class change Enable bit. When set, the CLSCn bits in Detection Event register only
indicates when the result of the most current classification operation differs from the result
of the previous one.
1 = CLSCn bit is set only when a change of class occurred for the associated channel.
0 = CLSCn bit is set each time a classification cycle occurred for the associated
channel.
2
DECHE
R/W
0
Detect Change Enable bit. When set, the DETCn bits in Detection Event register only
indicates when the result of the most current detection operation differs from the result of
the previous one.
1 = DETCn bit is set only when a change in detection occurred for the associated
channel.
0 = DETCn bit is set each time a detection cycle occurred for the associated channel.
1
–
R/W
0
0
–
R/W
0
SPACE
NOTE
If the MbitPrty bit needs to be changed from 0 to 1, make sure the OSS input pin is in the
idle (low) state for a minimum of 200 µsec prior to setting the MbitPrty bit, to avoid any
misbehavior related to loss of synchronization with the OSS bit stream.
NOTE
Only the nbitACC bit for channels 1-4 needs to be set to enable 16-bit I2C operation.
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Table 26. nbitACC = 1: Register Operations in 8-Bit (Config A) and 16-bit (Config B) I2C Mode
Cmd
Code
Register or Command Name
Configuration A (8-bit)
00h
INTERRUPT
INT bits P1-4, P5-8
01h
INTERRUPT MASK
MSK bits P1-4, P5-8
POWER EVENT
PGC_PEC P4-1, P8-5
DETECTION EVENT
CLS_DET P4-1, P8-5
FAULT EVENT
DIS_PCUT P4-1, P8-5
START/ILIM EVENT
ILIM_STR P4-1, P8-5
SUPPLY/FAULT EVENT
TSD, VDUV, VDUW, VPUV , RAMFLT
PCUT34, PCUT12, PCUT78, PCUT56,
OSSE4-1, OSSE8-5
0Ch
CHANNEL 1 DISCOVERY
CLS&DET1_CLS&DET5
0Dh
CHANNEL 2 DISCOVERY
CLS&DET2_CLS&DET6
0Eh
CHANNEL 3 DISCOVERY
CLS&DET3_CLS&DET7
0Fh
CHANNEL 4 DISCOVERY
CLS&DET4_CLS&DET8
10h
POWER STATUS
PG_PE P4-1, P8-5
Separate status byte per group of 4 channels
11h
PIN STATUS
AUTO,A4-A1,A0
Both 8-bit registers (channel 1 to 4 and channel 5 to 8) will
show the same result, except that A0 = 0 (channel 1 to 4) or
1 (channel 5 to 8).
12h
OPERATING MODE
MODE P4-1, P8-5
Separate Mode byte per group of 4 channels.
13h
DISCONNECT ENABLE
DCDE P4-1, P8-5
Separate DC disconnect enable byte per group of 4 channels.
14h
DETECT/CLASS ENABLE
CLE_DETE P4-1, P8-5
Separate Detect/Class Enable byte per group of 4 channels.
15h
PWRPR/2P-PCUT DISABLE
OSS_DCUT P4-1, P8-5
Separate OSS/DCUT byte per group of 4 channels.
TIMING CONFIG
TLIM_TSTRT_TOVLD_TMPDO P4-1,
P8-5
Separate Timing byte per group of 4 channels.
02h
03h
04h
05h
06h
07h
08h
09h
0Bh
16h
Configuration B (16-bit)
Separate mask and interrupt result per group of 4 channels.
The Supply event bit is repeated twice.
Separate event byte per group of 4 channels.
0Ah
66
Bits Description
Both 8-bit registers (channel 1 to 4 and channel 5 to 8) will show the same results for TSD, VDUV, VPUV and RAMFLT.
The PCUTxx and OSSEx bits will. have separate status per group of 4 channels.
Clearing at least one VPUV/VDUV also clears the other one.
Separate Status byte per channel
Both 8-bit registers (channel 1 to 4 and channel 5 to 8) will
show the same result, including A0 = 0.
17h
GENERAL MASK
P4-1, P8-5 including n-bit access
Separate byte per group of 4 channels.
n-bit access: Setting this in at least one of the virtual quad register space is enough to enter Config B mode. To go back to
config A, clear both.
MbitPrty: Setting this in at least one of the virtual quad register space is enough to enter 3-bit shutdown priority. To go back
to 1-bit shutdown, clear both MbitPrty bits.
18h
DETECT/CLASS Restart
RCL_RDET P4-1, P8-5
Separate DET/CL RST byte per group of 4 channels
19h
POWER ENABLE
POF_PWON P4-1, P8-5
Separate POF/PWON byte per group of 4 channels
1Ah
RESET
P4-1, P8-5
Separate byte per group of 4 channels, Clear Int pin and
Clear All int.
1Bh
ID
1Ch
Autoclass and Connecttion Chech
Separate byte per group of 4 channels.
Both 8-bit registers (channel 1 to 4 and channel 5 to 8) will show the same result unless modified through I2C.
AC4-1, CC34 - 12, AC8-5, CC78-56
Separate byte per group of 4 channels.
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Table 26. nbitACC = 1: Register Operations in 8-Bit (Config A) and 16-bit (Config B) I2C Mode (continued)
Cmd
Code
Register or Command Name
Bits Description
Configuration A (8-bit)
Configuration B (16-bit)
1Eh
2P POLICE 1/5 CONFIG
POL1, POL5
1Fh
2P POLICE 2/6 CONFIG
POL2, POL6
20h
2P POLICE 3/7 CONFIG
POL3, POL7
21h
2P POLICE 4/8 CONFIG
POL4, POL8
22h
CAP MEASUREMENT
CDET4-1, CDET8-5
Separate capacitance measurement enable bytes per group of 4 channels.
Power-on FAULT
PF P4-1, P8-5
Separate Power-on FAULT byte per group of 4 channels
26h
PORT REMAPPING
Logical P4-1, P8-5
Separate Remapping byte per group of 4 channels.
Reinitialized only if POR or RESET pin. Kept unchanged if 0x1A IC reset or CPU watchdog reset.
27h
Multi-Bit Priority 21 / 65
MBP2-1, MBP6-5
Separate MBP byte per group of 2 channels
28h
Multi-Bit Priority 43 / 87
MBP4-3, MBP8-7
Separate MBP byte per group of 2 channels
29h
PORT POWER ALLOCATION
4PW34-12, MC34-12, 4PW78-56, MC7856
Separate 4Pnn, MCnn byte per group of 4 channels
2Ah
4P POLICE 12 / 56 CONFIG
POL12, POL56
Separate 4P Policing byte per channel
2Bh
4P POLICE 34 / 78CONFIG
POL34, POL78
Separate 4P Policing byte per channel
2Ch
TEMPERATURE
TEMP P1-4, P5-8
Both 8-bit registers (channel 1 to 4 and channel 5 to 8) must show the same result.
4P FAULT CONFIG
NLM4-1, NCT4-1, 4PPCT4-1,DCDT4-1,
NLM8-5, NCT8-5, 4PPCT8-5,DCDT8-5
Separate fault handling byte per group of 4 channels
INPUT VOLTAGE
VPWR P1-4, P5-8
Both 8-bit registers (channel 1 to 4 and channel 5 to 8) must show the same result.
24h
25h
2Dh
2Eh
2Fh
30h
CHANNEL 1 CURRENT
I1, I5
31h
32h
CHANNEL 1 VOLTAGE
V1, V5
33h
34h
CHANNEL 2 CURRENT
I2, I6
35h
36h
CHANNEL 2 VOLTAGE
V2, V6
37h
38h
CHANNEL 3 CURRENT
I3, I7
39h
3Ah
CHANNEL 3 VOLTAGE
3Bh
V3, V7
Separate Policing byte per channel.
Separate 2-byte per group of 4 channels
Separate 2-byte per group of 4 channels.
2-byte Read at 0x30 gives I1
4-byte Read at 0x30 gives I1, I5.
N/A
2-byte Read at 0x31 gives I5.
Separate 2-byte per group of 4 channels
2-byte Read at 0x32 gives V1
4-byte Read at 0x32 gives V1, V5.
N/A
2-byte Read at 0x33 gives V5.
Separate 2-byte per group of 4 channels
2-byte Read at 0x34 gives I2
4-byte Read at 0x34 gives I2, I6.
N/A
2-byte Read at 0x35 gives I6.
Separate 2-byte per group of 4 channels
2-byte Read at 0x36 gives V2
4-byte Read at 0x36 gives V2, V6.
N/A
2-byte Read at 0x37 gives V6.
Separate 2-byte per group of 4 channels
2-byte Read at 0x38 gives I3
4-byte Read at 0x38 gives I3, I7.
N/A
2-byte Read at 0x39 gives I7.
Separate 2-byte per group of 4 channels
2-byte Read at 0x3A gives V3
4-byte Read at 0x3A gives V3, V7.
N/A
2-byte Read at 0x3B gives V7.
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Table 26. nbitACC = 1: Register Operations in 8-Bit (Config A) and 16-bit (Config B) I2C Mode (continued)
Cmd
Code
3Ch
Register or Command Name
CHANNEL 4 CURRENT
Bits Description
I4, I8
3Dh
3Eh
Configuration B (16-bit)
Separate 2-byte per group of 4 channels
2-byte Read at 0x3C gives I4
4-byte Read at 0x3C gives I4, I8.
N/A
2-byte Read at 0x3D gives I8.
Separate 2-byte per group of 4 channels
2-byte Read at 0x3E gives V4
4-byte Read at 0x3E gives V4, V8.
N/A
2-byte Read at 0x3F gives V8.
CHANNEL 4 VOLTAGE
V4, V8
40h
OPERATIONAL FOLDBACK
2xFB4-1, 2xFB8-5
Separate 2xFBn config byte per group of 4 channels.
41h
FIRMWARE REVISION
FRV P1-4, P5-8
Both 8-bit registers (channel 1 to 4 and channel 5 to 8) must show the same result.
42h
I2C WATCHDOG
P1-4, P5-8
IWD3-0: if at least one of the two 4-port settings is different than 1011b, the watchdog is enabled for all 8 channels.
WDS: Both 8-bit registers (channel 1 to 4 and channel 5 to 8) must show the same WDS result. Each WDS bit needs to be
cleared individually through I2C.
43h
DEVICE ID
DID_SR P1-4, P5-8
Both 8-bit registers (channel 1 to 4 and channel 5 to 8) will show the same result .
44h
CHANNEL 1 RESISTANCE
RDET1, RDET5
45h
CHANNEL 2 RESISTANCE
RDET2, RDET6
46h
CHANNEL 3 RESISTANCE
RDET3, RDET7
3Fh
68
Configuration A (8-bit)
Separate byte per channel.
Detection resistance always updated, detection good or bad.
47h
CHANNEL 4 RESISTANCE
RDET4, RDET8
4Ch
CHANNEL 1 ASSIGNED CLASS
ACLS&PCLS1_ACLS&PCLS5
4Dh
CHANNEL 2 ASSIGNED CLASS
ACLS&PCLS2_ACLS&PCLS6
4Eh
CHANNEL 3 ASSIGNED CLASS
ACLS&PCLS3_ACLS&PCLS7
4Fh
CHANNEL 4 ASSIGNED CLASS
ACLS&PCLS4_ACLS&PCLS8
50h
AUTOCLASS CONTROL
MAC4-1, AAC4-1, MAC8-5, AAC8-5
51h
AUTOCLASS POWER 1/5
PAC1, PAC5
52h
AUTOCLASS POWER 2/6
PAC2, PAC6
53h
AUTOCLASS POWER 3/7
PAC3, PAC7
54h
AUTOCLASS POWER 4/8
PAC4, PAC8
55h
ALTERNATIVE FOLDBACK
ALTFB4-1, ALTIR4-1, ALTFN8-5,
ALTIR8-5
Separate Alternative Foldback byte per group of 4 channels
60h
SRAM CONTROL
SRAM CNTRL BITS
These bits must be configured for the lower virtual quad (A0=0, CH 1-4)). These bits have no functionality for the upper
virtual quad (A0=1, Ch 5-8) device
61h
SRAM DATA
Streaming data input is independent of I2C configuration
62h
START ADDRESS (LSB)
These bits must be configured for the lower virtual quad (A0=0, CH 1-4)). These bits have no functionality for the upper
virtual quad (A0=1, Ch 5-8) device
63h
START ADDRESS (MSB)
These bits must be configured for the lower virtual quad (A0=0, CH 1-4)). These bits have no functionality for the upper
virtual quad (A0=1, Ch 5-8) device
Separate Status byte per channel
Separate Auto Class control bytes per 4 channels
Separate Auto Class Power Measurement byte per channel
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9.6.2.20 DETECT/CLASS RESTART Register
COMMAND = 18h with 1 Data Byte, Write Only
Push button register.
Each bit corresponds to a particular cycle (detect or class restart) per channel. Each cycle can be individually
triggered by writing a 1 at that bit location, while writing a 0 does not change anything for that event.
In Diagnostic/Manual mode, a single cycle (detect or class restart) will be triggered when these bits are set while
in Semi Auto mode, it sets the corresponding bit in the Detect/Class Enable register 0x14.
A Read operation will return 00h.
During tOVLD, tLIM or tSTART cool down cycle, any Detect/Class Restart command for that channel will be accepted
but the corresponding action will be delayed until end of cool-down period.
Figure 64. DETECT/CLASS RESTART Register Format
7
RCL4
W-0
6
RCL3
W-0
5
RCL2
W-0
4
RCL1
W-0
3
RDET4
W-0
2
RDET3
W-0
1
RDET2
W-0
0
RDET1
W-0
LEGEND: R/W = Read/Write; R = Read only; W = Write only; -n = value after reset
Table 27. DETECT/CLASS RESTART Register Field Descriptions
Bit
Field
7–4
RCL4–RCL1
Type
W
Reset Description
0
Restart classification bit
3–0
RDET4–RDET1
W
0
Restart detection bits
SPACE
These bits may be used in place of completing a "Read-Modify-Write" sequence in register 0x14 to enable
detection and classification on a per channel basis.
For 4-pair wired ports in Semi Auto or Auto mode, both bits need to be set in order for Detection or Classification
to be enabled
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9.6.2.21 POWER ENABLE Register
COMMAND = 19h with 1 Data Byte, Write Only
Push button register.
Used to initiate a channel(s) turn on or turn off in any mode except OFF mode.
Figure 65. POWER ENABLE Register Format
7
POFF4
W-0
6
POFF3
W-0
5
POFF2
W-0
4
POFF1
W-0
3
PWON4
W-0
2
PWON3
W-0
1
PWON2
W-0
0
PWON1
W-0
LEGEND: R/W = Read/Write; R = Read only; W = Write only; -n = value after reset
Table 28. POWER ENABLE Register Field Descriptions
Bit
Field
7–4
POFF4–POFF1
Type
W
Reset Description
0
Channel power off bits
3–0
PWON4–PWON1
W
0
Channel power on bits
SPACE
NOTE
Writing a “1” at POFFn and PWONn on same Channel during the same write operation
turns the Channel off.
NOTE
The tOVLD, tLIM, tSTART and disconnect events have priority over the PWON command.
During tOVLD, tLIM or tSTART, cool down cycle, any channel turn on using Power Enable
command will be ignored and the Channel will be kept off.
NOTE
For 4-Pair wired ports:
These bits control the individual Channel response of each Channel. Thus it is
recommended that for 4-pair wire ports, the bits for both channels be set
simultaneously.
In Semi Auto mode with DETE = CLE = 1 on both channels, it is permissible to set
only one PWON bit to attempt to turn on only that singular channel.
For 4P Single Signature devices that classify as class 5-8, a singular PWON
command will fail and a STRT fault set with the “insufficient power” code written to
0x24.
If the PD presents itself as class 4 or below, then only that pair set will be
powered.
Setting the alternate PWON bit for the secondary channel of a single
signature device after the primary is already powered will result in the
immediate turn on of the channel without completing DET or CLS.
For a 4-Pair Dual Signature device that has only one channel powered, setting the
PWON bit for the unpowered channel will result in a turn on attempt on that channel
based on the assigned classification of the other channel and the Power Allocation
settings in 0x29h at the time of the new PWON command.
PWONn in Diagnostic/Manual Mode:
If the PSE controller is configured in Diagnostic mode, writing a “1” at that PWONn bit location will immediately
turn on the associated Channel.
SPACE
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PWONn in Semi Auto Mode:
While in Semi Auto mode, writing a “1” at a PWONn bit will attempt to turn on the associated Channel. If the
detection or class results are invalid, the Channel is not turned on, and there will be no additional attempts to
turn on the Channel until this push button is reasserted and the channel will resume its configured semi auto
mode operation.
NOTE
In Semi Auto mode, the Power Allocation (0x29h) value needs to be set prior to issuing a
PWON command. Any changes to the Power Allocation value after a PWON command is
given may be ignored.
Table 29. Channel Response to PWONn Command in Semi Auto Mode
CLEn
DETEn
Channel Operation
Result of PWONn Command
0
0
Idle
Singular Turn On attempted with Full DET
and CLS cycle
0
1
Cycling Detection Measurements only
Singular Turn On attempted with Full DET
and CLS cycle
1
0
Idle
Singular Turn On attempted with Full DET
and CLS cycle
1
1
Cycling Detection and Classification
Measurements
Singular Turn On attempted after next (or
current) DET and CLS cycle
In semi auto mode with DETE and CLE set, as long as the PWONx command is received prior to the start of
classification, the Channel will be powered immediately after classification is complete provided the classification
result is valid and the power allocations settings (see register 0x29h) are sufficient to enable power on.
SPACE
PWONn in Auto Mode:
In Auto mode with DETE or CLE set to 0, a PWONx command will initiate a singular detection and classification
cycle and the port/channel will be powered immediately after classification is complete provided the classification
result is valid and the power allocations settings (see register 0x29h) are sufficient to enable power on.
In Auto mode with DETE and CLE = 1, there is no need for a PWON command. The port/channel will
automatically attempt to turn on after each detection and classification cycle.
NOTE
In Auto mode, the Power Allocation (0x29h) value needs to be set prior to issuing a
PWON command. Any changes to the Power Allocation value after a PWON command is
given may be ignored.
A singular PWONn command will be ignored for a 4-Pair wired port in Auto mode.
Table 30. Channel Response to PWONn Command in Auto Mode
CLEn
DETEn
Channel Operation
Result of PWONn Command
0
0
Idle
Singular Turn On attempted with Full DET
and CLS cycle
0
1
Cycling Detection Measurements only
Singular Turn On attempted with Full DET
and CLS cycle
1
0
Idle
Singular Turn On attempted with Full DET
and CLS cycle
1
1
Cycling Detection and Classification
Measurements
NA - Channel will power automatically after
a valid detection and classification
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PWOFFn in any Mode:
The channel is immediately disabled and the following registers are cleared:
Table 31. Channel Turn Off with PWOFFn Command
Register
Bits to be Reset
0x04
CLSCn and DETCn
0x06
DISFn and PCUTn
0x08
STRTn and ILIMn
0x0A/B
0x0C-0F
PCUTnn
Requested Class and Detection
0x10
PGn and PEn
0x14
CLEn and DETEn
0x1C
ACn and CCnn
0x1E-21
0x24
0x2A-2B
0x2D
0x30-3F
0x40
2P Policing set to 0xFFh
PFn
4P Policing set to 0xFFh
NLMnn, NCTnn, 4PPCTnn, and DCDTnn
Channel Voltage and Current Measurements
2xFBn
0x44 - 47
Detection Resistance Measurements
0x4C-4F
Assigned Class and Previous Class
0x51-54
Autoclass Measurement
NOTE
It may take upwards of 5ms after PWOFFn command for all register values to be updated.
Only the bits associated with the channel/port ("n") with PWOFFn set will be cleared. Those bits associated with
channels/ports remaining in operation will not be changed.
These bits control the response of each channel individually. Thus, it is recommended that for 4-pair wire ports,
the bits for both channels be set simultaneously.
NOTE
If only one channel of a 4-pair single signature load with a Class 5 or higher assigned
class is given a PWOFFn command, both channels will be disabled.
In the event a singular channel of a 4-pair dual signature PD is turned off due to a PWOFFn command, the
power may be reapplied to that channel by setting the PWON bit in 0x19h provided the detection and
classification are still valid and the Power Allocation settings in 0x29 are sufficient based on the assigned
classification of the powered channel.
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9.6.2.22 RESET Register
COMMAND = 1Ah with 1 Data Byte, Write Only
Push button register.
Writing a 1 at a bit location triggers an event while a 0 has no impact. Self-clearing bits.
Figure 66. RESET Register Format
7
CLRAIN
W-0
6
CLINP
W-0
5
–
W-0
4
RESAL
W-0
3
RESP4
W-0
2
RESP3
W-0
1
RESP2
W-0
0
RESP1
W-0
LEGEND: R/W = Read/Write; R = Read only; W = Write only; -n = value after reset
Table 32. RESET Register Field Descriptions
Bit
Field
Type
Reset Description
7
CLRAIN
W
0
Clear all interrupts bit. Writing a 1 to CLRAIN clears all event registers and all bits in the
Interrupt register. It also releases the INT pin
6
CLINP
W
0
When set, it releases the INT pin without any impact on the Event registers nor on the
Interrupt register.
5
–
W
0
4
RESAL
W
0
Reset all bits when RESAL is set. Results in a state similar to a power-up reset. Note that
the VDUV and VPUV bits (Supply Event register) follow the state of VDD and VPWR
supply rails.
RESP4–RESP1
W
0
Reset channel bits. Used to force an immediate channel(s) turn off in any mode, by writing
a 1 at the corresponding RESPn bit location(s).
3–0
Note: For a 4-pair wired port, setting a RESPn bit for either channel will result in both
channels being reset.
Setting the RESAL bit will result in all of the I2C register being restored to the RST condition with the exception
of those in the following table:
Register
0x00
0x0A/B
Bits
RESAL Result
All
TSD, VPUV, VDWRN, and VPUV
0x26
All
0x2C and 0x2E
All
0x41
All
Pre RESAL value will remain
NOTE
Setting the RESAL bit for only one group of four channels (1-4 or 5-8) will result in only
those four channels being reset.
NOTE
After using the CLINP command, the INT pin will not be reasserted for any interrupts until
all existing interrupts have been cleared.
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Setting the RESPn bit will immediate turn off the associated channel and clear the registers according to the
following table:
Table 33. Channel Turn Off with RESPn Command
Register
Bits to be Reset
0x04
CLSCn and DETCn
0x06
DISFn and PCUTn
0x08
STRTn and ILIMn
0x0A/B
0x0C-0F
PCUTnn
Requested Class and Detection
0x10
PGn and PEn
0x14
CLEn and DETEn
0x1C
ACn and CCnn
0x1E-21
0x24
0x2A-2B
0x2D
0x30-3F
0x40
2P Policing set to 0xFFh
PFn
4P Policing set to 0xFFh
NLMnn, NCTnn, 4PPCTnn, and DCDTnn
Channel Voltage and Current Measurements
2xFBn
0x44 - 47
Detection Resistance Measurements
0x4C-4F
Assigned Class and Previous Class
0x51-54
Autoclass Measurement
SPACE
NOTE
Only the bits associated with the channel/port ("n") with RESPn set will be cleared. Those
bits associated with channels/ports remaining in operation will not be changed.
it may take upwards of 5 ms before all of the registers are cleared following a RESPn
command.
The RESPn command will cancel any ongoing cool down cycles .
Users need to wait at least 3ms before trying to reenable discovery or power on ports
following a RESPn command.
74
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9.6.2.23 ID Register
COMMAND = 1Bh with 1 Data Byte, Read/Write
Figure 67. ID Register Format
7
6
R/W-0
R/W-1
5
MFR ID
R/W-0
4
3
2
R/W-1
R/W-0
R/W-1
1
ICV
R/W-0
0
R/W-1
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 34. ID Register Field Descriptions
Bit
Field
Type
Reset Description
7–3
MFR ID
R/W
01010 Manufacture Identification number (0101,0)
b
2–0
ICV
R/W
101b
IC version number (011)
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9.6.2.24 Connection Check and Auto Class Status Register
COMMAND = 1Ch with 1 Data Byte, Read Only
Figure 68. Connection Check and Auto Class Register Format
7
AC4
R-0
6
AC3
R-0
5
AC2
R-0
4
AC1
R-0
3
CC34_2
R-0
2
CC34_1
R-0
1
CC12_2
R-0
0
CC12_1
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 35. Connection Check and Auto Class Field Descriptions
Bit
Field
Type
7–4
ACn
R
Reset Description
0000b Auto Class Detection Status
1 = PD supports Auto Class
0 = PD does not support Auto Class
3–2
CC34_2/1
R
00b
Connection Check result for 4-Pair port (channels 3 and 4)
1-0
CC12_2/1
R
00b
Connection Check result for 4-Pair port (channels 1 and 2)
Auto Class:
The auto class detection measurement is completed at the end of the long classification finger, and if a PD is
determined to support auto class, an auto class power measurement will be automatically completed after turn
on in accordance with the IEEE auto class timing requirements.
NOTE
The auto class function is operational regardless if a port is wired for 2-Pair or 4-Pair
operation.
For 4-Pair single signature devices, both ACn bits will report the same result even though
the classification measurement was completed on one channel.
An Auto Class power measurement will be completed shortly after power on for all
channels that are found to support auto class during classification.
These measurement results are available in registers (0x51h – 0x54h), and the auto class
power measurements are provide per individual channel.
Connection Check:
A connection check measurement will only be performed on 4-pair wired ports after at least one channel is found
to have a valid detection result.
The results of connection check
CCnn_2
CCnn_1
CC Result
0
0
"unknown" or incomplete
0
1
Single Signature
1
0
Dual Signature
1
1
Reserved
These bits will be set following the completion of a connection check and prior to the setting of the Detection
Event bits in the Detection Event register (0x04h).
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9.6.2.25 2-Pair Police Ch-1 Configuration Register
COMMAND = 1Eh with 1 Data Byte, Read/Write
Figure 69. 2-Pair Police Ch-1 Register Format
7
POL1_7
R/W-1
6
POL1_6
R/W-1
5
POL1_5
R/W-1
4
POL1_5
R/W-1
3
POL1_3
R/W-1
2
POL1_2
R/W-1
1
POL1_1
R/W-1
0
POL1_0
R/W1
1
POL2_1
R/W-1
0
POL2_0
R/W1
1
POL3_1
R/W-1
0
POL3_0
R/W1
1
POL4_1
R/W-1
0
POL4_0
R/W1
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.26 2-Pair Police Ch-2 Configuration Register
COMMAND = 1Fh with 1 Data Byte, Read/Write
Figure 70. 2-Pair Police Ch-2 Register Format
7
POL2_7
R/W-1
6
POL2_6
R/W-1
5
POL2_5
R/W-1
4
POL2_4
R/W-1
3
POL2_3
R/W-1
2
POL2_2
R/W-1
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.27 2-Pair Police Ch-3 Configuration Register
COMMAND = 20h with 1 Data Byte, Read/Write
Figure 71. 2-Pair Police Ch-3 Register Format
7
POL3_7
R/W-1
6
POL3_6
R/W-1
5
POL3_5
R/W-1
4
POL3_5
R/W-1
3
POL3_3
R/W-1
2
POL3_2
R/W-1
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.28 2-Pair Police Ch-4 Configuration Register
COMMAND = 21h with 1 Data Byte, Read/Write
Figure 72. 2-Pair Police Ch-4 Register Format
7
POL4_7
R/W-1
6
POL4_6
R/W-1
5
POL4_5
R/W-1
4
POL4_4
R/W-1
3
POL4_3
R/W-1
2
POL4_2
R/W-1
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 36. 2-Pair Policing Register Fields Descriptions
Bit
Field
Type
7–0
POLn_7POLn_0
R/W
Reset Description
1
1-byte defining 2-Pair PCUT minimum threshold.
The equation defining the PCUT is:
PCUT = (N × PCSTEP)
Where, when assuming 0.200-Ω Rsense resistor is used:
PCSTEP = 0.5 W
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SPACE
NOTE
These bits set the minimum threshold for the design. Internally, the typical PCUT threshold
is set slightly above this value to ensure that the device does not trip a Pcut fault at or
below the set value in this register due to part to part or temperature variation.
For 4-pair wired ports, the 2P Policing values are still applied to the individual channels.
See the description for registers 0x2Ah and 0x2Bh for more information on 4-Pair Policing.
The contents of this register is reset to 0xFFh anytime the port is turned off or disabled
either due to fault condition or user command
NOTE
Programmed values of less than 2W are not supported. If a value of less than 2W is
programmed into these registers, the device will use 2W as the 2-pair Policing value.
SPACE
Power Policing:
The TPS23881 implements a true Power Policing limit, where the device will adjust the policing limit based on
both voltage and current variation in order to ensure a reliable power limit.
In Semi Auto and Auto modes, these bits are automatically set during power on based on the assigned class
(see tables below). If an alternative value is desired, it needs to be set after the PEn bit is set in 0x10h, or it may
also be configured prior to port turn on in combination with the use of the MPOLn bits in register 0x40 (see 2x
FOLDBACK SELECTION Register).
Table 37. 2-Pair Policing Settings for 2-Pair Wired Ports and 4-Pair Dual Signature Devices
Assigned Class
POLn7-0 Settings
Minimum Power
Class 1
0000 1000
4W
Class 2
0000 1110
7W
Class 3
0001 1111
15.5W
Class 4
0011 1100
30W
Class 5 Dual Signature
0101 1010
45W
Table 38. 2-Pair Policing Settings for 4-Pair Wired Port with Single Signature Devices
(1)
(2)
78
Assigned Class
POLn7-0 Settings
Minimum Power
Class 1
0000 1000
4W (1)
Class 2
0000 1110
7W (1)
Class 3
0001 1111
15.5W (1)
Class 4
0011 1100
30W (1)
Class 5
0100 0000
32W (2)
Class 6
0100 1110
39W (2)
Class 7
0101 1001
44.5W (2)
Class 8
0110 1011
53.5W (2)
Both channels of a 4-Pair port with a single signature device and an assigned class of 1-4 are required to support the full classification
current per pair set.
4-Pair ports with a single signature device and an assigned class of 5-8 are required to satisfy the IEEE load imbalance requirements for
4-Pair powered devices.
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9.6.2.29 Capacitance (Legacy PD) Detection
COMMAND = 22h with 1 Data Byte, Write Only
Used to do enable capacitance measurement from Maunal mode
Figure 73. Capacitance Detection Register Format
7
R/W-0
6
CDET4
R/W-0
5
R/W-0
4
CDET3
R/W-0
3
R/W-0
2
CDET2
R/W-0
1
R/W-0
0
CDET1
R/W-0
LEGEND: R/W = Read/Write; R = Read only; W = Write only; -n = value after reset
Table 39. Capacitance Detection Register Field Descriptions
Field
Type
7, 5,
3, 1
Bit
Reserved
R/W
Reset Description
0
6, 4,
2, 0
CDETn
R/W
0
Enables Capacitance defection for channel "n"
0 = Capacitance defection disabled
1 = Capacitance detection enabled
To complete a capacitance measurement on a channel, the channel must first be placed into diagnostic mode.
Set the bits in register 0x22h to enable capacitance detection on the channel(s) desired. Then set the DETE bits
in register 0x14h to begin the detection and process.
NOTE
The TPS23881 SRAM needs to be programmed in order for the capacitance
measurement to operate properly.
The capacitance measurement is only supported in Manual/Diagnostic mode.
No capacitance measurement will be made if the result of the resistance detection is
returned as "valid".
For 4P wired ports, the capacitance measurement needs to be completed on each
channel individually.
Upon completion of the capacitance measurement the DETCn bit will bet in register 0x04h, and the resistance
and capacitance values will be updated in registers 0x44h - 0x4Bh.
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9.6.2.30 Power-on Fault Register
COMMAND = 24h with 1 Data Byte, Read Only
COMMAND = 25h with 1 Data Byte, Clear on Read
Figure 74. Power-on Fault Register Format
7
6
5
PF4
R-0
CR-0
4
3
PF3
R-0
CR-0
R-0
CR-0
2
1
PF2
R-0
CR-0
R-0
CR-0
0
PF1
R-0
CR-0
R-0
CR-0
R-0
CR-0
LEGEND: R/W = Read/Write; R = Read only; W = Write only; CR = Clear on Read; -n = value after reset
Table 40. Power-on Fault Register Field Descriptions
Bit Field
7–0 PF4–PF1
Type
Reset
R or CR
0
Description
Represents the fault status of the classification and detection for channel n, following a failed turn
on attempt with the PWONn command. These bits are cleared when channel n is turned off.
PFn: the selection is as follows:
Fault Code
Power-on Fault Description
0
0
No fault
0
1
Invalid detection
1
0
Classification Error
1
1
Insufficient Power
SPACE
NOTE
When a Start Fault occurs and the PECn bit is not set, then this register will indicate the
cause of the fault.
An insufficient power fault is reported anytime the reg 0x29 configuration will not allow a
channel to be powered. See the section describing Power Allocation and Power Demotion.
For 4-pair wired Ports:
Thee bits will be updated individually for dual signature connected devices
Thee bits will be updated concurrently for single signature connected devices
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9.6.2.31 PORT RE-MAPPING Register
COMMAND = 26h with 1 Data Byte, Read/Write
Figure 75. PORT RE-MAPPING Register Format
7
6
Physical Channel # of Logical
Channel 4
R/W-1
R/W-1
5
4
Physical Channel # of Logical
Channel 3
R/W-1
R/W-0
3
2
Physical Channel # of Logical
Channel 2
R/W-0
R/W-1
1
0
Physical Channel # of Logical
Channel 1
R/W-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; W = Write only; CR = Clear on Read; -n = value after reset
Table 41. PORT RE-MAPPING Register Field Descriptions
Bit
Field
Type
7–0 Physical
Channel # of
Logical
Channel n
R/W
POR /
RST
Description
1110 Used to re-map channels logically due to physical board constraints. Re-mapping is between any
0100b channel within 4-channel group (1-4 or 5-8). All channels of a group of four must be in OFF mode
/P
prior to receiving the port re-mapping command, otherwise the command will be ignored. By default
there is no re-mapping.
Each pair of bits corresponds to the logical port assigned.
The selection per port is as follows:
Re-Map
Code
Physical
Channel
Package Pins
0
0
1
Drain1,Gat1,Sen1
0
1
2
Drain2,Gat2,Sen2
1
0
3
Drain3,Gat3,Sen3
1
1
4
Drain4,Gat4,Sen4
When there is no re-mapping the default value of this register is 1110,0100. The 2 MSbits with a
value 11 indicate that logical channel 4 is mapped onto physical channel #4, the next 2 bits, 10,
suggest logical channel 3 is mapped onto physical channel #3 and so on.
Note: Code duplication is not allowed – that is, the same code cannot be written into the remapping
bits of more than one port – if such a value is received, it will be ignored and the chip will stay with
existing configuration.
Note: Port remapping configuration is kept unchanged if 0x1A IC reset command is received.
SPACE
NOTE
The RST condition of "P" indicates that the previous state of these bits will be preserved
following a device reset using the RESET pin. Thus, pulling the RESET input low will not
overwrite any user changes to this register.
NOTE
Only logical Channels 3 and 4 and 1 and 2 may be wired as 4-pair Ports.
Unpredictable behavior will occur if any other combinations of logical Channels are
wired in a 4-pair configuration.
NOTE
After port remapping, TI recommends to do at least one detection-classification cycle
before turn on.
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9.6.2.32 Channels 1 and 2 Multi Bit Priority Register
COMMAND = 27h with 1 Data Byte, Read/Write .
Figure 76. Channels 1 and 2 MBP Register Format
7
–
R/W-0
6
MBP2_2
R/W-0
5
MBP2_1
R/W-0
4
MBP2_0
R/W-0
3
–
R/W-0
2
MBP1_2
R/W-0
1
MBP1_1
R/W-0
0
MBP1_0
R/W–0
1
MBP3_1
R/W-0
0
MBP3_0
R/W–0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
SPACE
9.6.2.33 Channels 3 and 4 Multi Bit Priority Register
COMMAND = 28h with 1 Data Byte, Read/Write
Figure 77. Channels 3 and 4 MBP Register Format
7
–
R/W-0
6
MBP4_2
R/W-0
5
MBP4_1
R/W-0
4
MBP4_0
R/W-0
3
–
R/W-0
2
MBP3_2
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 42. Channels n MBP Register Field Descriptions
Bit
Field
Type
7–0
MBPn_2-0
R/W
Reset Description
0
MBPn_2-0: Multi Bit Priority bits, three bits per channel, if 3-bit shutdown priority has been selected
(MbitPrty in General Mask register is high). It is used to determine which channel(s) is (are) shut down
in response to a serial shutdown code received at the OSS shutdown input.
The turn off procedure (including register bits clearing) is similar to a channel reset using Reset
command (1Ah register), except that it does not cancel any ongoing fault cool down time count.
The priority is defined as followings:
OSS code ≤ MBPn_2-0 : when the OSS code is received, the corresponding channel is powered
off.
OSS code > MBPn_2-0 : OSS code has no impact on the channel
MBPn_2-0 0x27/28
Register
Multi Bit Priority OSS Code for Channel Off
0
0
0
Highest
0
0
1
2
OSS = ‘000’
OSS = ‘000’ or ‘001’
0
1
0
3
OSS ≤ ‘010’
0
1
1
4
OSS ≤ ‘011’
1
0
0
5
OSS ≤ ‘100’
1
0
1
6
OSS = any code except ‘111’
1
1
1
Lowest
OSS = any code
The priority reduces as the 3-bit value increases. Thus, a channel with a "000" setting has the highest priority,
while one with a "111" setting has the lowest.
It is permissible to apply the same settings to multiple channels. Doing so will result in all channels with the same
setting will be disabled when the appropriate OSS code is presented.
For 4-pair wired Ports, these bits control the individual Channel response. In order for both pair sets of a 4-pair
wire Port to be disabled, both channels need to have the same MBP setting otherwise it is possible for only one
pair set to be disabled.
In the event a singular channel of a 4-pair dual signature PD is turned off due to OSS or other reason, power
may be reapplied to that channel by setting the PWON bit in 0x19h provided the detection and classification are
still valid and the Power Allocation settings in 0x29 are sufficient based on the assigned classification of the
powered channel.
82
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The turn off procedure due to OSS is similar to a channel reset or change to OFF mode, with the exception that
OSS does not cancel any ongoing fault cool down timers. the table below includes the bits that will be cleared
when a channel is disabled due to OSS:
Table 43. Channel Turn Off with MBP OSS
Register
Bits to be Reset
0x04
CLSCn and DETCn
0x06
DISFn and PCUTn
0x08
STRTn and ILIMn
0x0A/B
0x0C-0F
PCUTnn
Requested Class and Detection
0x10
PGn and PEn
0x14
CLEn and DETEn
0x1C
ACn and CCnn
0x1E-21
0x24
0x2A-2B
0x2D
0x30-3F
0x40
2P Policing set to 0xFFh
PFn
4P Policing set to 0xFFh
NLMnn, NCTnn, 4PPCTnn, and DCDTnn
Channel Voltage and Current Measurements
2xFBn
0x44 - 47
Detection Resistance Measurements
0x4C-4F
Assigned Class and Previous Class
0x51-54
Autoclass Measurement
SPACE
NOTE
There is no memory of any preceding 3-bit OSS commands. Each 3-bit OSS command is
processed immediately (prior to the end of the last OSS MBP pulse) based on the MBPn
settings for each Channel. Any attempt to shutdown additional Channels thereafter will
require additional 3-bit OSS commands.
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9.6.2.34 4-Pair Wired and Port Power Allocation Register
COMMAND = 29h with 1 Data Byte, Read/Write
Figure 78. 4-Pair Wired and Power Allocation Register Format
7
4PW34
R/W-0
6
MC34_2
R/W-0
5
MC34_1
R/W-0
4
MC34_0
R/W-0
3
4PW12
R/W-0
2
MC12_2
R/W-0
1
MC12_1
R/W-0
0
MC12_0
R/W–0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 44. 4-Pair Wired and Power Allocation Register Field Descriptions
Bit
7,3
Field
Type
Reset
4PWnn
R/W
0
Description
4-Pair wired configuration bits
4PWnn = 1: Channels 3/4 or 1/2 are wired in a 4-pair configuration
4PWnn = 0: Channels 3/4 or 1/2 are wired in 2-pair configurations
6 - 4 , MCnn_2-0
2-0
R/W
0
MCnn_2-0: Port Power Allocation bits. These bits set the maximum power classification level that
a given Port (2-Pair or 4-Pair) is allowed to power on
In Semi Auto mode these bits need to be set prior to issuing a PWONn command, while in Auto
mode these bits need to be set prior to setting the DETE and CLE bits in 0x14.
Table 45. 4-Pair Wired and Power Allocation Settings
4PWnn
MCnn_2
MCnn_1
MCnn_0
0
0
0
0
Power Allocation
2-Pair 15.4W
0
0
0
1
Reserved
0
0
1
0
Reserved
0
0
1
1
2-Pair 30W
0
1
x
x
Reserved
1
0
0
0
4-Pair 15.4W
1
0
0
1
Reserved
1
0
1
0
Reserved
1
0
1
1
4-Pair 30W (Class 4)
1
1
0
0
4-Pair 45W (Class 5)
1
1
0
1
4-Pair 60W (Class 6)
1
1
1
0
4-Pair 75W (Class 7)
1
1
1
1
4-Pair 90W (Class 8)
SPACE
Refer to Table 1 and Table 2 for more details on the application of Power Demotion and the relationship between
the Power Allocation settings and the resulting Assigned Class.
SPACE
NOTE
In order to prevent any unexpected behavior the setting the 4PWnn bits should only be
done immediately following a Power On Reset (POR) event while the ports are still in OFF
mode.
NOTE
The Power Allocation (0x29h) value needs to be set prior to issuing a PWON command in
Semi Auto or Auto modes, and prior to setting the DETE and CLE bits in Auto mode. Any
changes to the Power Allocation value after a PWON command is given may be ignored.
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NOTE
For 4-pair dual signature PDs, the odd numbered Channels takes priority over the even
numbered Channels. Thus, an even numbered Channel will be powered based on the
difference between the total power allocated and what the odd Channel classified as.
For example if a dual signature PD contained two 45W PDs and the PSEs power
allocation was set to 60W, the odd numbered Channel will be powered at 45W while the
even numbered Channel will be limited to 15W.
NOTE
For 2-Pair wired ports, the MCnn_2-0 bits set the power allocation settings for both
channels 1 and 2 and 3 and 4 concurrently.
It is possible to have channels 3 and 4 set to 15.4W while channels 1 and 2 are set to
30W, but it is not possible to have different power allocation settings between channels 1
and 2 or 3 and 4
SPACE
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9.6.2.35 4-Pair Police Ch-1 and 2 Configuration Register
COMMAND = 2Ah with 1 Data Byte, Read/Write
Figure 79. 4-Pair Police Ch-1 and 2 Configuration Register Format
7
POL12_7
R/W-1
6
POL12_6
R/W-1
5
POL12_5
R/W-1
4
POL12_5
R/W-1
3
POL12_3
R/W-1
2
POL12_2
R/W-1
1
POL12_1
R/W-1
0
POL12_0
R/W1
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.36 4-Pair Police Ch-3 and 4 Configuration Register
COMMAND = 2Bh with 1 Data Byte, Read/Write
Figure 80. 4-Pair Police Ch-3 and 4 Configuration Register Format
7
POL34_7
R/W-1
6
POL34_6
R/W-1
5
POL34_5
R/W-1
4
POL34_4
R/W-1
3
POL34_3
R/W-1
2
POL34_2
R/W-1
1
POL34_1
R/W-1
0
POL34_0
R/W1
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 46. 4-Pair Police Register Field Descriptions
Bit
Field
Type
7–0
POLnn_7POLnn_0
R/W
Reset Description
1
1-byte defining the summed 4-Pair PCUT minimum threshold.
The equation defining the PCUT is:
PCUT = (N × PCSTEP)
Where, when assuming 0.200-Ω Rsense resistor is used:
PCSTEP = 0.5 W
SPACE
NOTE
These bits set the minimum threshold for the design. Internally, the typical PCUT threshold
is set slightly above this value to ensure that the device does not trip a Pcut fault at or
below the set value in this register due to part to part or temperature variation.
For 4-pair wired, the 2P Policing values are still applied to the individual Channels. See
the description for registers 0x1Eh through 0x21h for more information on 2-Pair Policing.
The contents of this register is reset to 0xFFh anytime the port is turned off or disabled
either due to fault condition or user command
NOTE
Programmed values of less than 4W are not supported. If a value of less than 4W is
programmed into these registers, the device will use 4W as the 4-pair Policing value.
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4-Pair Power Policing:
The TPS23881 implements a true Power Policing limit, where the device will adjust the policing limit based on
both voltage and sum of current variation in order to ensure a reliable power limit.
In Semi Auto and Auto modes, these bits are automatically set during power on based on the assigned class
(see Table 47). If an alternative value is desired, it needs to be set after the PEn bit is set in register 0x10h, or it
may also be configured prior to port turn on in combination with the use of the MPOLn bits in register 0x40 (see
2x FOLDBACK SELECTION Register).
Table 47. 4-Pair Policing Settings for 4-Pair Wired Port with Single Signature Devices
Assigned Class
POLnn7-0 Settings
Minimum Power
Class 1
0000 1000
4W
Class 2
0000 1110
7W
Class 3
0001 1111
15.5W
Class 4
0011 1100
30W
Class 5
0101 1010
45W
Class 6
0111 1000
60W
Class 7
1001 0110
75W
Class 8
1011 0100
90W
For a 4-pair dual signature devices, these values will be set based on the sum of the assigned classes of both
channels, but 4P PCut will be disabled (4PPCTnn bit in 0x2D = 0) by default as the primary policing method for
dual signature devices will be the 2-Pair values defined in registers 0x1Eh - 0x21h.
Setting the 4PPCTnn bit in 0x2D will enable 4P Policing if desired.
NOTE
The tOVLD time for 4-pair Pcut faults will be equal to the tOVLD setting + approximately 6 ms
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9.6.2.37 TEMPERATURE Register
COMMAND = 2Ch with 1 Data Byte, Read Only
Figure 81. TEMPERATURE Register Format
7
TEMP7
R-0
6
TEMP6
R-0
5
TEMP5
R-0
4
TEMP4
R-0
3
TEMP3
R-0
2
TEMP2
R-0
1
TEMP1
R-0
0
TEMP0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 48. TEMPERATURE Register Field Descriptions
Bit
Field
7–0
TEMP7–TEMP0
Type
Reset
R
0
Description
Bit Descriptions: Data conversion result. The I2C data transmission is a 1-byte transfer.
8-bit Data conversion result of temperature, from –20°C to 125°C. The update rate is
around once per second.
The equation defining the temperature measured is:
T = –20 + N × TSTEP
Where TSTEP is defined below as well as the full scale value:
88
Mode
Full Scale Value
TSTEP
Any
146.2°C
0.652°C
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9.6.2.38
SLVSF02C – MARCH 2019 – REVISED OCTOBER 2019
4-Pair Fault Configuration Register
COMMAND = 2Dh with 1 Data Byte, Read/Write
Figure 82. 4-Pair Fault Configuration Register Format
7
NLM34
R/W-0
6
NLM12
R/W-0
5
NCT34
R/W-0
4
NCT12
R/W-0
3
4PPCT34
R/W-0
2
4PPCT12
R/W-0
1
DCDT34
R/W-0
0
DCDT12
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 49. 4-Pair Fault Register Field Descriptions
Bit
7,6
Field
Type
NLMnn
R/W
Reset Description
0
4-Pair ILIM Fault Management bits
1 = Both channels on a 4-Pair wired port will be disabled if an ILIM fault occurs on
either channel
0 = Only the channel on which the ILIM fault occurred will be disabled. The alterative
channel will remain powered.
In Auto mode these bits will be automatically set after turn on if a 4-Pair Single Signature
device is powered
5,4
NCTnn
R/W
0
4-Pair PCUT Fault Management bits
1 = Both channels on a 4-Pair wired port will be disabled if a 2-Pair PCUT fault occurs
on either channel
0 = Only the channel on which the 2-Pair PCUT fault occurred will be disabled. The
alterative channel will remain powered.
In Auto mode these bits will be automatically set after turn on if a 4-Pair Single Signature
device is powered
3, 2
4PPCTnn
R/W
0
4-Pair Summed PCUT Enable bits
1 = Summed 4-Pair PCut is enabled
0 = Summed 4-Pair PCut is disabled
The hardware continue to monitor for ILIM faults independent of these bits
In either Auto and Semi Auto modes, these bits will be automatically set to a "1" after turn
on if a 4-Pair Single Signature device is powered
1,0
DCDTnn
R/W
0
DC Disconnect Threshold bits
1 = DC disconnect Threshold set to 4.5mA typical
0 = DC disconnect Threshold set to 6.5mA typical
For 4-pair Dual Signature PDs, the DCDTxx bit will be set to “1” during turn on and the
disconnect threshold will be applied independently per Channel. Thus, if either channel falls
below the 4.5mA threshold for the duration of TMPDO + TMPS, only that channel will be
disabled while the alternative channel remains powered as long it it satisfies.
For 4-pair single signature PDs (see register 0x1Ch), these bits are internally set during
power on based on the assigned class (0x4C-4F):
Assigned Classes 1-4: DCDTxx = 0
Assigned Classes 5-8: DCDTxx = 1
SPACE
NOTE
Partial Disconnect: For 4-pair single signature PDs with DCDTxx = 0 and an Assigned
Class = 0-4, one pair set/channel will be immediately disabled when either channel falls
below the DC Disconnect threshold to improve the low current measurement accuracy.
The second channel will remain powered as long as the current drawn by the load
satisfies the MPS timing and current requirements. The disabled channel will be reenabled when the single channel current increases above 75 mA.
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NOTE
4-pair Pcut is disabled whenever a 4-pair port is either in a partial disconnect state or one
or both channel currents are below 30mA (typ).
NOTE
For 4-pair single signature PDs with DCDTxx = 1 and an Assigned Class = 5-8, both
channels will remain powered until the current on both channels fall below the 4.5mA
threshold for the duration of TMPDO + TMPS.
NOTE
Setting DCDTxx = “0” for a 4P Dual Signature PD or 4P Single Signature PD with
assigned class = 5-8 after turn on will result in the use of the 6.5mA threshold per channel
which is non-compliant to the 802.3bt standard.
NOTE
For 4-pair Dual Signature PDs,the disconnect threshold will be applied independently per
channel. Thus, if either channel falls below the disconnect threshold for the duration of
TMPDO + TMPS, only that channel will be disabled while the alternative channel remains
powered as long it continues to satisfy the MPS timing and current requirements.
NOTE
DC Disconnect for 4-Pair ports power on in Manual/Diagnostic mode will behave as
independent channels. Thus, if either channel current falls below VIMIN for longer than
tMPDO , that channel will be disabled and a disconnect fault will be set (DISFn bits in
register 0x06/7).
SPACE
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9.6.2.39 INPUT VOLTAGE Register
COMMAND = 2Eh with 2 Data Byte (LSByte first, MSByte second), Read only
Figure 83. INPUT VOLTAGE Register Format
7
LSB:
VPWR7
R-0
MSB:
–
R-0
6
5
4
3
2
1
0
VPWR6
R-0
VPWR5
R-0
VPWR4
R-0
VPWR3
R-0
VPWR2
R-0
VPWR1
R-0
VPWR0
R-0
–
R-0
VPWR13
R-0
VPWR12
R-0
VPWR11
R-0
VPWR10
R-0
VPWR9
R-0
VPWR8
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 50. INPUT VOLTAGE Register Field Descriptions
Bit
13–0
Field
VPWR13- VPWR0
Type
Reset
R
0
Description
Bit Descriptions: Data conversion result. The I2C data transmission is a 2-byte transfer.
14-bit Data conversion result of input voltage.
The equation defining the voltage measured is:
V = N × VSTEP
Where VSTEP is defined below as well as the full scale value:
Mode
Full Scale Value
VSTEP
Any
60 V
3.662 mV
Note that the measurement is made between VPWR and AGND.
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9.6.2.40 CHANNEL 1 CURRENT Register
COMMAND = 30h with 2 Data Byte, (LSByte First, MSByte second), Read Only
Figure 84. CHANNEL 1 CURRENT Register Format
7
6
5
4
3
2
1
0
I1_7
R-0
I1_6
R-0
I1_5
R-0
I1_4
R-0
I1_3
R-0
I1_2
R-0
I1_1
R-0
I1_0
R-0
–
R-0
–
R-0
I1_13
R-0
I1_12
R-0
I1_11
R-0
I1_10
R-0
I1_9
R-0
I1_8
R-0
LSB:
MSB:
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.41 CHANNEL 2 CURRENT Register
COMMAND = 34h with 2 Data Byte, (LSByte First, MSByte second), Read Only
Figure 85. CHANNEL 2 CURRENT Register Format
7
6
5
4
3
2
1
0
I2_7
R-0
I2_6
R-0
I2_5
R-0
I2_4
R-0
I2_3
R-0
I2_2
R-0
I2_1
R-0
I2_0
R-0
–
R-0
–
R-0
I2_13
R-0
I2_12
R-0
I2_11
R-0
I2_10
R-0
I2_9
R-0
I2_8
R-0
LSB:
MSB:
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.42 CHANNEL 3 CURRENT Register
COMMAND = 38h with 2 Data Byte, (LSByte First, MSByte second), Read Only
Figure 86. CHANNEL 3 CURRENT Register Format
7
6
5
4
3
2
1
0
I3_7
R-0
I3_6
R-0
I3_5
R-0
I3_4
R-0
I3_3
R-0
I3_2
R-0
I3_1
R-0
I3_0
R-0
–
R-0
–
R-0
I3_13
R-0
I3_12
R-0
I3_11
R-0
I3_10
R-0
I3_9
R-0
I3_8
R-0
LSB:
MSB:
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.43 CHANNEL 4 CURRENT Register
COMMAND = 3Ch with 2 Data Byte, (LSByte First, MSByte second), Read Only
Figure 87. CHANNEL 4 CURRENT Register Format
7
6
5
4
3
2
1
0
I4_7
R-0
I4_6
R-0
I4_5
R-0
I4_4
R-0
I4_3
R-0
I4_2
R-0
I4_1
R-0
I4_0
R-0
–
R-0
–
R-0
I4_13
R-0
I4_12
R-0
I4_11
R-0
I4_10
R-0
I4_9
R-0
I4_8
R-0
LSB:
MSB:
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
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Table 51. CHANNEL n CURRENT Register Field Descriptions
Bit
13-0
Field
In_13- In_0
Type
Reset
R
0
Description
Bit Descriptions: Data conversion result. The I2C data transmission is a 2-byte transfer.
Note that the conversion is done using a TI proprietary multi-slope integrating converter.
14-bit Data conversion result of current for channel n. The update rate is around once per 100
ms in powered state.
The equation defining the current measured is:
I = N × ISTEP
Where ISTEP is defined below as well as the full scale value, according to the operating mode:
Mode
Full Scale Value
ISTEP
Powered and
Classification
1.46 A (with 0.200-Ω
Rsense)
89.5 µA
Note: in any of the following cases, the result through I2C interface is automatically 0000
channel is in OFF mode
channel is OFF while in semiauto mode and detect/class is not enabled
channel is OFF while in semiauto mode and detection result is incorrect
In diagnostic/manual mode, if detect/class has been enabled at least once, the register retains
the result of the last measurement
SPACE
NOTE
1.46A is the theoretical full scale range of the ADC based on 14bits * Istep. However, due
to the 1.25A channel current limit, the channel current will foldback and be disabled when
the current exceeds the ILIM-2X threshold (VLIM2X).
NOTE
For 4-Pair wired ports, these registers still only provide the individual per channel current
measurements. The value from both channels need to be added together in order to get
the total 4-pair port current reading.
SPACE
Class Current Reading
Following the completion of any classification measurement on a channel, the measured classification current is
reported in these registers until either a port current reading is completed following a port turn on or the port is
disabled.
NOTE
Only the current measurement for the last classification finger is reported. Thus, for a
single signature Class 5, 6, 7, and 8 PDs, the reported classification current will report a
Class 0, 1, 2, & 3 current level respectively.
NOTE
The scaling factor for the class current reading is decreased by a factor of 10x to
8.95uA/bit.
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9.6.2.44 CHANNEL 1 VOLTAGE Register
COMMAND = 32h with 2 Data Byte, (LSByte First, MSByte second), Read Only
Figure 88. CHANNEL 1 VOLTAGE Register Format
7
6
5
4
3
2
1
0
V1_6
R-0
V1_5
R-0
V1_4
R-0
V1_3
R-0
V1_2
R-0
V1_1
R-0
V1_0
R-0
–
R-0
V1_13
R-0
V1_12
R-0
V1_11
R-0
V1_10
R-0
V1_9
R-0
V1_8
R-0
LSB:
V1_7
R-0
MSB:
–
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.45 CHANNEL 2 VOLTAGE Register
COMMAND = 36h with 2 Data Byte, (LSByte First, MSByte second), Read Only
Figure 89. CHANNEL 2 VOLTAGE Register Format
7
6
5
4
3
2
1
0
V2_6
R-0
V2_5
R-0
V2_4
R-0
V2_3
R-0
V2_2
R-0
V2_1
R-0
V2_0
R-0
–
R-0
V2_13
R-0
V2_12
R-0
V2_11
R-0
V2_10
R-0
V2_9
R-0
V2_8
R-0
LSB:
V2_7
R-0
MSB:
–
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.46 CHANNEL 3 VOLTAGE Register
COMMAND = 3Ah with 2 Data Byte, (LSByte First, MSByte second), Read Only
Figure 90. CHANNEL 3 VOLTAGE Register Format
7
6
5
4
3
2
1
0
V3_6
R-0
V3_5
R-0
V3_4
R-0
V3_3
R-0
V3_2
R-0
V3_1
R-0
V3_0
R-0
–
R-0
V3_13
R-0
V3_12
R-0
V3_11
R-0
V3_10
R-0
V3_9
R-0
V3_8
R-0
LSB:
V3_7
R-0
MSB:
–
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.47 CHANNEL 4 VOLTAGE Register
COMMAND = 3Eh with 2 Data Byte, (LSByte First, MSByte second), Read Only
Figure 91. CHANNEL 4 VOLTAGE Register Format
7
6
5
4
3
2
1
0
V4_6
R-0
V4_5
R-0
V4_4
R-0
V4_3
R-0
V4_2
R-0
V4_1
R-0
V4_0
R-0
–
R-0
V4_13
R-0
V4_12
R-0
V4_11
R-0
V4_10
R-0
V4_9
R-0
V4_8
R-0
LSB:
V4_7
R-0
MSB:
–
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
94
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Table 52. CHANNEL n VOLTAGE Register Field Descriptions
Bit
13-0
Field
Vn_13- Vn_0
Type
Reset
R
0
Description
Bit Descriptions: Data conversion result. The I2C data transmission is a 2-byte transfer.
The equation defining the voltage measured is:
V = N × VSTEP
Where VSTEP is defined below as well as the full scale value:
Mode
Full Scale Value
VSTEP
Powered
60 V
3.662 mV
Note that a powered voltage measurement is made between VPWR and DRAINn.
Note: if a channel is OFF, the result through I2C interface is automatically 0000.
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9.6.2.48 2x FOLDBACK SELECTION Register
COMMAND = 40h with1 Data Byte Read/Write
Figure 92. 2x FOLDBACK SELECTION Register Format
7
2xFB4
R/W-0
6
2xFB3
R/W-0
5
2xFB2
R/W-0
4
2xFB1
R/W-0
3
MPOL4
R/W -0
2
MPOL3
R/W -0
1
MPOL2
R/W -0
0
MPOL1
R/W -0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 53. 2x FOLDBACK SELECTION Register Field Descriptions
Bit
Field
Type
Reset
7–4
2xFB4- 2xFB1
R/W
0
Description
When set, this activates the 2x Foldback mode for a channel which increases its ILIM and
ISHORT levels normal settings, as shown in Figure 40. Note that the fault timer starts when the
ILIM threshold is exceeded.
Notes:
1) At turn on, the inrush current profile is unaffected by these bits, as shown in Figure 39.
2) When a 2xFBn bit is deasserted, the tLIM setting used for the associated channel is
always the nominal value (approximately 60 ms). If 2xFBn bit is asserted, then tLIM for
associated channel is programmable as defined in the Timing Configuration register
(0x16).
3) If the assigned class for a channel is class 4 or above, the 2xFB bit will be automatically
set during turn on.
For a single signature 4-pair powered PD both bits will be set
For a dual signature 4-pair powered PD each Channel will be set according to the
individually assigned PD classification
3-0
MPOL4 MPOL1
R/W
0
Manual Policing and Foldback configuration bits
0 = The internal device firmware automatically adjusts the Policing (PCUT) and 2xFBn
settings based on the assigned class during port turn on
1 = The Policing (PCUT) and 2xFBn settings will not be changed during port turn on.
Note: Independent of these settings, the Policing (PCUT) and 2xFBn settings are returned to
their default values upon port turn off.
Note: Setting either bit for a 4P configured port disables the automatic configuration on both
channels
The MPOLn bits are cleared upon port turn off.
NOTE
For 4-pair wired Ports the 2xFBn bits individually control each Channels operation.
1.3
0.5
0.475
0.45
0.425
0.4
0.375
0.35
0.325
0.3
0.275
0.25
0.225
0.2
0.175
0.15
0.125
0.1
0.075
0.05
0.025
0
2xFBn =0, ALTFBn = 0
2xFBn =0, ALTFBn = 1
1.1
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
3
6
9
12
15
18
21
24
27
30
VDRAIN (V)
33
36
39
42
45
48
51
54
57
0
0
3
6
9
D201
Figure 93. 1x Mode (2xFBn = 0) Foldback Curves, IPORT vs
VDRAIN
96
2xFBn =1, ALTFBn = 0
2xFBn =1, ALTFBn = 1
1.2
IPORT (A)
IPORT (A)
Refer to register 0x55h description for more information on additional Foldback and Inrush
configuration options
12
15
18
21
24
27
30
VDRAIN (V)
33
36
39
42
45
48
51
54
57
D202
Figure 94. 2x Mode (2xFBn = 1) Foldback Curves, IPORT vs
VDRAIN
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9.6.2.49 FIRMWARE REVISION Register
COMMAND = 41h with 1 Data Byte, Read Only
Figure 95. FIRMWARE REVISION Register Format
7
6
5
4
3
2
1
0
FRV
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 54. FIRMWARE REVISION Register Field Descriptions
Bit
Field
Type
7–0
FRV
R
Reset Description
Firmware Revision number
After a RESET or POR fault this value will default to 0000, 0000b, but upon a “valid” SRAM load, this value will
reflect the corresponding SRAM version of firmware (0x01h – 0xFEh).
NOTE
If the value of this register = 0xFFh, the device is running in “safe mode”, and the SRAM
needs to be reprogrammed to resume normal operation.
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9.6.2.50 I2C WATCHDOG Register
COMMAND = 42h with 1 Data Byte, Read/Write
The I2C watchdog timer monitors the I2C clock line in order to prevent hung software situations that could leave
ports in a hazardous state. The timer can be reset by either edge on SCL input. If the watchdog timer expires, all
channels will be turned off and WDS bit will be set. The nominal watchdog time-out period is 2 seconds.
Figure 96. I2C WATCHDOG Register Format
7
–
–
6
–
–
5
–
–
4
IWDD3
R/W-1
3
IWDD2
R/W-0
2
IWDD1
R/W-1
1
IWDD0
R/W-1
0
WDS
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 55. I2C WATCHDOG Register Field Descriptions
Bit
Field
Type
Reset Description
4–1
IWDD3–IWDD0
R/W
1011b I2C Watchdog disable. When equal to 1011b, the watchdog is masked. Otherwise, it is
umasked and the watchdog is operational.
WDS
R/W
0
0
I2C Watchdog timer status, valid even if the watchdog is masked. When set, it means that
the watchdog timer has expired without any activity on I2C clock line. Writing 0 at WDS
location clears it.
Note that when the watchdog timer expires and if the watchdog is unmasked, all channels
are also turned off.
When the channels are turned OFF due to I2C watchdog, the corresponding bits are also cleared:
Table 56. I2C WATCHDOG Reset
Register
Bits to be Reset
0x04
CLSCn and DETCn
0x06
DISFn and PCUTn
0x08
STRTn and ILIMn
0x0A/B
0x0C-0F
PCUTnn
Requested Class and Detection
0x10
PGn and PEn
0x14
CLEn and DETEn
0x1C
ACn and CCnn
0x1E-21
0x24
0x2A-2B
0x2D
0x30-3F
0x40
2P Policing set to 0xFFh
PFn
4P Policing set to 0xFFh
NLMnn, NCTnn, 4PPCTnn, and DCDTnn
Channel Voltage and Current Measurements
2xFBn
0x44 - 47
Detection Resistance Measurements
0x4C-4F
Assigned Class and Previous Class
0x51-54
Autoclass Measurement
The corresponding PGCn and PECn bits of Power Event register will also be set if there is a change. The
corresponding PEn and PGn bits of Power Status Register are also updated accordingly.
NOTE
If the I2C watchdog timer has expired, the Temperature and Input voltage registers will
stop being updated until the WDS bit is cleared. The WDS bit must then be cleared to
allow these registers to work normally.
98
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9.6.2.51 DEVICE ID Register
COMMAND = 43h with 1 Data Byte, Read Only
Figure 97. DEVICE ID Register Format
7
6
5
4
3
2
1
DID
0
SR
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 57. DEVICE ID Register Field Descriptions
Bit
Field
7–5
DID
Type
R
0010b Device ID number
Reset Description
4–0
SR
R
0010b Silicon Revision number
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9.6.2.52 CHANNEL 1 DETECT RESISTANCE Register
COMMAND = 44h with 1 Data Byte, Read Only
Figure 98. CHANNEL 1 DETECT RESISTANCE Register Format
7
R1_7
R-0
6
R1_6
R-0
5
R1_5
R-0
4
R1_4
R-0
3
R1_3
R-0
2
R1_2
R-0
1
R1_1
R-0
0
R1_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.53 CHANNEL 2 DETECT RESISTANCE Register
COMMAND = 45h with 1 Data Byte, Read Only
Figure 99. CHANNEL 2 DETECT RESISTANCE Register Format
7
R2_7
R-0
6
R2_6
R-0
5
R2_5
R-0
4
R2_4
R-0
3
R2_3
R-0
2
R2_2
R-0
1
R2_1
R-0
0
R2_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.54 CHANNEL 3 DETECT RESISTANCE Register
COMMAND = 46h with 1 Data Byte, Read Only
Figure 100. CHANNEL 3 DETECT RESISTANCE Register Format
7
R3_7
R-0
6
R3_6
R-0
5
R3_5
R-0
4
R3_4
R-0
3
R3_3
R-0
2
R3_2
R-0
1
R3_1
R-0
0
R3_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.55 CHANNEL 4 DETECT RESISTANCE Register
COMMAND = 47h with 1 Data Byte, Read Only
Figure 101. CHANNEL 4 DETECT RESISTANCE Register Format
7
R4_7
R-0
6
R4_6
R-0
5
R4_5
R-0
4
R4_4
R-0
3
R4_3
R-0
2
R4_2
R-0
1
R4_1
R-0
0
R4_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 58. DETECT RESISTANCE Register Fields Descriptions
Bit
Field
7-0
Rn_7- Rn_0
Type
Reset
R
0
Description
8-bit data conversion result of detection resistance for channel n.
Most recent 2-point Detection Resistance measurement result. The I2C data transmission is a
1-byte transfer.
Note that the register content is not cleared at turn off.
The equation defining the resistance measured is:
R = N × RSTEP
Where RSTEP is defined below as well as the full scale value:
100
Useable Resistance Range
RSTEP
2 kΩ to 50 kΩ
195.3125 Ω
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9.6.2.56 CHANNEL 1 DETECT CAPACITANCE Register
COMMAND = 48h with 1 Data Byte, Read Only
Figure 102. CHANNEL 1 DETECT CAPACITANCE Register Format
7
C1_7
R-0
6
C1_6
R-0
5
C1_5
R-0
4
C1_4
R-0
3
C1_3
R-0
2
C1_2
R-0
1
C1_1
R-0
0
C1_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.57 CHANNEL 2 DETECT CAPACITANCE Register
COMMAND = 49h with 1 Data Byte, Read Only
Figure 103. CHANNEL 2 DETECT CAPACITANCE Register Format
7
C2_7
R-0
6
C2_6
R-0
5
C2_5
R-0
4
C2_4
R-0
3
C2_3
R-0
2
C2_2
R-0
1
C2_1
R-0
0
C2_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.58 CHANNEL 3 DETECT CAPACITANCE Register
COMMAND = 4Ah with 1 Data Byte, Read Only
Figure 104. CHANNEL 3 DETECT CAPACITANCE Register Format
7
C3_7
R-0
6
C3_6
R-0
5
C3_5
R-0
4
C3_4
R-0
3
C3_3
R-0
2
C3_2
R-0
1
C3_1
R-0
0
C3_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.59 CHANNEL 4 DETECT CAPACITANCE Register
COMMAND = 4Bh with 1 Data Byte, Read Only
Figure 105. CHANNEL 4 DETECT CAPACITANCE Register Format
7
C4_7
R-0
6
C4_6
R-0
5
C4_5
R-0
4
C4_4
R-0
3
C4_3
R-0
2
R4_2C
R-0
1
C4_1
R-0
0
C4_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 59. DETECT CAPACITANCE Register Fields Descriptions
Bit
Field
7-0
Cn_7- Cn_0
Type
Reset
R
0
Description
8-bit data conversion result of capacitance measurement for channel n.
Most recent capacitance measurement result. The I2C data transmission is a 1-byte transfer.
The equation defining the resistance measured is:
C = N × CSTEP
Where CSTEP is defined below as well as the full scale value:
Useable Resistance Range
CSTEP
1 µF to 12 µF
0.05 µF
Note that the register content is not cleared at turn off.
Note: The capacitance measurement is only supported in Manual/Diagnostic mode.
Note: No capacitance measurement will be made if the result of the resistance detection is
returned as "valid".
Note: The TPS23881 SRAM needs to be programmed in order for the capacitance
measurement to operate properly.
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9.6.2.60 CHANNEL 1 ASSIGNED CLASS Register
COMMAND = 4Ch with 1 Data Byte, Read Only
Figure 106. CHANNEL 1 ASSIGNED CLASS Register Format
7
6
5
4
3
2
ACLASS Ch1
R-0
R-0
1
0
R-0
R-0
1
0
R-0
R-0
1
0
R-0
R-0
1
0
R-0
R-0
PCLASS Ch1
R-0
R-0
R-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.61 CHANNEL 2 ASSIGNED CLASS Register
COMMAND = 4Dh with 1 Data Byte, Read Only
Figure 107. CHANNEL 2 ASSIGNED CLASS Register Format
7
6
5
4
3
2
ACLASS Ch2
R-0
R-0
PCLASS Ch2
R-0
R-0
R-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.62 CHANNEL 3 ASSIGNED CLASS Register
COMMAND = 4Eh with 1 Data Byte, Read Only
Figure 108. CHANNEL 3 ASSIGNED CLASS Register Format
7
6
5
4
3
2
ACLASS Ch3
R-0
R-0
PCLASS Ch3
R-0
R-0
R-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.63 CHANNEL 4 ASSIGNED CLASS Register
COMMAND = 4Fh with 1 Data Byte, Read Only
Figure 109. CHANNEL 4 ASSIGNED CLASS Register Format
7
6
5
4
3
2
ACLASS Ch4
R-0
R-0
PCLASS Ch4
R-0
R-0
R-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Bit Descriptions: These bits represent the "assigned" and previous classification results for channel n. These
bits are cleared when channel n is turned off.
102
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Table 60. CHANNEL n ASSIGNED CLASS Register Field Descriptions
Bit Field
Type Reset
7–4 ACLASS
Ch-n
R
3–0 PCLASS
Ch-n
R
0
Description
Assigned classification on channel n.
See Table 61 below
0
Previous Class result on channel n.
See Table 62 below
Table 61. Assigned Class Designations
ACLASS-Chn
Assigned Class
Bit 7
Bit 6
Bit 5
Bit 4
0
0
0
0
Unknown
0
0
0
1
Class 1
0
0
1
0
Class 2
0
0
1
1
Class 3
0
1
0
0
Class 4
0
1
0
1
Reserved
0
1
1
0
Reserved
0
1
1
1
Reserved
1
0
0
0
Class 5 - 4-Pair Single Signature
1
0
0
1
Class 6 - 4-Pair Single Signature
1
0
1
0
Class 7 - 4-Pair Single Signature
1
0
1
1
Class 8 - 4-Pair Single Signature
1
1
0
0
Reserved
1
1
0
1
Class 5 - 4-Pair Dual Signature
1
1
1
0
Reserved
1
1
1
1
Reserved
Table 62. Previous Class Designations
PCLASS-Chn
Previous Class
Bit 7
Bit 6
Bit 5
Bit 4
0
0
0
0
Unknown
0
0
0
1
Class 1
0
0
1
0
Class 2
0
0
1
1
Class 3
0
1
0
0
Class 4
0
1
0
1
Reserved
0
1
1
0
Class 0
0
1
1
1
Reserved
1
0
0
0
Class 5 - 4-Pair Single Signature
1
0
0
1
Class 6 - 4-Pair Single Signature
1
0
1
0
Class 7 - 4-Pair Single Signature
1
0
1
1
Class 8 - 4-Pair Single Signature
1
1
0
0
Reserved
1
1
0
1
Class 5 - 4-Pair Dual Signature
1
1
1
0
Reserved
1
1
1
1
Reserved
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“Requested” vs. “Assigned” Classification:
The “requested” class is the classification the PSE measures during Mutual Identification prior to turn on,
whereas the “assigned” class is the classification level the Channel was powered on with based on the Power
Allocation setting in register 0x29h. The “requested” classification values are available in registers 0x0C-0F
For a 4-pair single signature device, both channels will report the same assigned PD classification within 5ms
after classification is completed. However, only the channel that classification was measured on will have the
CLSCn bit set in register 0x04h
For a 4-pair dual signature device each Channel will reports is own individually assigned PD classification within
5ms of turn on.
NOTE
Upon being powered, devices that present a class 0 signature during discovery will be
given an assigned class of "Class 3"
NOTE
There is no Assigned Class assigned for ports/channels powered out of Manual/Diagnostic
mode. Any settings such as the port power policing and 1x/2x foldback selection that are
typically configure based on the assigned class result need to manually configured by the
user.
Previous Classification
In certain circumstances the requested class result in 0x0C-0F can not properly reflect the actual classification of
the PD connected to the port/channel. This will happen when a port has a power allocation limit of 15.4W and the
PSE can only provide 1 classification finger during turn on. When this occurs and if the device is configured to
run in Semi Auto mode with det and cls enabled, the 3-finger classification measurement that preceded the turn
on detection and classification cycle will be stored here. This information can be useful in scenarios where a port
had to be demoted to stay under the system power limit at turn on but additional power budget comes available
later on.
NOTE
The Previous Classification results are only valid for channels being used in semi auto
mode with ongoing discovery (DETE and CLE = 1).
104
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9.6.2.64 AUTO CLASS CONTROL Register
COMMAND = 50h with 1 Data Byte, Read/Write
Figure 110. AUTO CLASS CONTROL Register Format
7
MAC4
R/W-0
6
MAC3
R/W-0
5
MAC2
R/W-0
4
MAC1
R/W-0
3
AAC4
R/W-0
2
AAC3
R/W-0
1
AAC2
R/W-0
0
AAC1
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 63. AUTO CLASS CONTROL Register Field Descriptions
Bit
Field
Type
7-4
MACn
R/W
Reset Description
0
Manual Auto Class Measurement bits
1 = Manual Auto Class Measurement enabled
0 = Manual Auto Class measurement complete
The auto class measurement will begin within 10ms of this bit being set.
This bit will be cleared by the internal firmware within 1ms of the updated Autoclass
measurement result(s) in 0x51-54h.
3 -0
AACn
R/W
0
Auto Class Auto Adjustment Enable bits
1 = Autoclass auto adjust is enabled and the corresponding PCUT settings will be
automatically adjusted based on the measured autoclass power
0 = Autoclass auto adjust is disabled and it is up to the user to adjust the value of
PCUT as desired.
SPACE
NOTE
Any MACn bits set prior to turn on will be ignored and cleared during turn on.
Auto Class Pcut Adjustments:
If the ACx bit(s) are set in register 0x50h, the TPS23881 will automatically adjust its PCUT value based on the
auto class power measurement (PAC in registers 0x51-54) and Any Automatic Auto Class facilitated (AACn = 1)
PCut adjustments will be made within 5 ms of the end of the auto class measurement period.
If the AACn bits are not set, the table and equations below should be used to make any PCUT adjustments
based on the auto class power measurement (PAC).
Table 64. Typical Auto Class Margins by Measured Power
Auto Class Measured Power (PAC)
PAC_MARGIN
PAC < 18.5 W
0.5 W
19 W < PAC < 25.5 W
1W
26 W < PAC < 36.5 W
2W
36.5 W < PAC < 45W
3W
45 W < PAC < 51.5 W
4W
51.5 W < PAC < 58 W
5W
58 W < PAC < 63W
6W
63 W < PAC < 68 W
7W
68 W < PAC < 73 W
8W
PAC > 73 W
9W
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SPACE
NOTE
For a PSE supporting Auto Class, the PAC_MARGIN is an IEEE required surplus of power
over the measured power during auto class that allows for component degradation over
time.
For 2-Pair or Dual Signature 4-Pair PDs, only the 2P-PCut values will be updated based on each pair sets
measured PAC according to the equation below.
2P-PCut = PAC + PAC_MARGIN
SPACE
For Single signature 4-Pair PDs, the sum of the autoclass power measurements on each pair set will be used to
determine the 4P-PCut setting according to the equation below:
4P-PCut = PAC_ALTA + PAC_ALTB + PAC_MARGIN
SPACE
For Single signature 4-Pair PDs, the auto class measurements will have no impact on the 2P-PCut settings.
These values will remain unchanged from the 2P-Pcut settings prior to the start of the auto class measurement.
NOTE
For 4-pair wired ports with single signature connected devices:
if only one AACn bit is set and an autoclass power measurement is completed
(manual or during turn on), the 4-PCut value will still be updated based on the power
measurement
If only one MACn bit is set, no autoclass measurement will be completed.
SPACE
NOTE
If the result of PAC + PAC_MARGIN is above a Channel’s assigned classification range, no
changes will be made to the either the 2P or 4P Pcut settings.
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9.6.2.65 CHANNEL 1 AUTO CLASS POWER Register
COMMAND = 51h with 1 Data Byte, Read Only
Figure 111. CHANNEL 1 AUTO CLASS POWER Register Format
7
R-0
6
PAC1_6
R-0
5
PAC1_5
R-0
4
PAC1_4
R-0
3
PAC1_3
R-0
2
PAC1_2
R-0
1
PAC1_1
R-0
0
PAC1_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.66 CHANNEL 2 AUTO CLASS POWER Register
COMMAND = 52h with 1 Data Byte, Read Only
Figure 112. CHANNEL 2 AUTO CLASS POWER Register Format
7
R-0
6
PAC2_6
R-0
5
PAC2_5
R-0
4
PAC2_4
R-0
3
PAC2_3
R-0
2
PAC2_2
R-0
1
PAC2_1
R-0
0
PAC2_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.67 CHANNEL 3 AUTO CLASS POWER Register
COMMAND = 53h with 1 Data Byte, Read Only
Figure 113. CHANNEL 3 AUTO CLASS POWER Register Format
7
R-0
6
PAC3_6
R-0
5
PAC3_5
R-0
4
PAC3_4
R-0
3
PAC3_3
R-0
2
PAC3_2
R-0
1
PAC3_1
R-0
0
PAC3_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.68 CHANNEL 4 AUTO CLASS POWER Register
COMMAND = 54h with 1 Data Byte, Read Only
Figure 114. CHANNEL 4 AUTO CLASS POWER Register Format
7
R-0
6
PAC4_6
R-0
5
PAC4_5
R-0
4
PAC4_4
R-0
3
PAC4_3
R-0
2
PAC4_2
R-0
1
PAC4_1
R-0
0
PAC4_0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 65. AUTO CLASS POWER Register Fields Descriptions
Bit
Field
6-0
PACn_6PACn_0
Type
Reset
R
0
Description
8-bit data conversion result of the auto class power measurement for channel n.
Peak average power calculation result from channel voltage and current data conversion
measurements taken during the auto class power measurement window.
The equation defining the auto class power measured is:
PAC= N × PAC_STEP
Where, when assuming 0.200-Ω Rsense resistor is used:
PCSTEP = 0.5 W
SPACE
NOTE
The IEEE requires a surplus of power (defined as PAC_MARGIN) to be available over the
measured auto class power to allow for component degradation over time. See Table 64
for the relationship between PAC and PAC_MARGIN
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9.6.2.69 ALTERNATIVE FOLDBACK Register
COMMAND = 55h with 1 Data Byte, Read/Write
Figure 115. ALTERNATIVE FOLDBACK Register Format
7
ALTFB4
R/W-0
6
ALTFB3
R/W-0
5
ALTFB2
R/W-0
4
ALTFB1
R/W-0
3
ALTIR4
R/W-0
2
ALTIR3
R/W-0
1
ALTIR2
R/W-0
0
ALTIR1
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 66. ALTERNATIVE FOLDBACK Register Field Descriptions
Bit
Field
7-4
ALTFBn
Type
Reset
R
0
Description
Alternative Foldback Enable bits: Used to enable the operational alterative foldback curves
while powered.
1 = Alternative Foldback is enabled
0 = Alternative Foldback is disabled
The ALTFBn bits should be set prior to issuing a PWONn command to ensure the desired
foldback curve is being used.
3-0
ALTIRn
R
0
Alternative Inrush Enable bits: Used to enable the alterative foldback curves during inrush on
channel n
1 = Alternative Inrush is enabled
0 = Alternative Inrush is disabled
Note: The ALTIRn bits need to be set prior to sending a PWONn command to ensure the
desired inrush behavior is followed
1.3
0.5
0.475
0.45
0.425
0.4
0.375
0.35
0.325
0.3
0.275
0.25
0.225
0.2
0.175
0.15
0.125
0.1
0.075
0.05
0.025
0
2xFBn =0, ALTFBn = 0
2xFBn =0, ALTFBn = 1
2xFBn =1, ALTFBn = 0
2xFBn =1, ALTFBn = 1
1.2
1.1
1
0.9
0.8
IPORT (A)
IPORT (A)
SPACE
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
3
6
9
12
15
18
21
24
27
30
VDRAIN (V)
33
36
39
42
45
48
51
54
0
57
0
3
6
9
12
15
18
21
24
D201
Figure 116. 1x Mode (2xFBn = 0) Foldback Curves, IPORT vs
VDRAIN
27
30
VDRAIN (V)
33
36
39
42
45
48
51
54
57
D202
Figure 117. 2x Mode (2xFBn = 1) Foldback Curves, IPORT vs
VDRAIN
0.55
ALTIRn = 0
ALTIRn = 1
0.5
0.45
0.4
IPORT (A)
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
0
3
6
9
12
15
18
21
24
27
30
VPORT (V)
33
36
39
42
45
48
51
54
57
D100
Figure 118. Inrush Foldback Curves, IPORT vs VPORT
108
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9.6.2.70 SRAM CONTROL Register
COMMAND = 60h with 1 Data Byte, Read/Write
Figure 119. SRAM CONTROL Register Format
7
PROG_SEL
R/W-0
6
CPU_RST
R/W-0
5
R/W-0
4
PAR_EN
R/W-0
3
RAM_EN
R/W-0
2
PAR_SEL
R/W-0
1
R/WZ
R/W-0
0
CLR_PTR
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 67. SRAM CONTROL Register Field Descriptions
Bit
7
Field
Type
PROG_SEL
R/W
Reset Description
0
I2C Programming select bit.
1 = SRAM I2C read/write is enabled
0 = SRAM I2C read/write is disabled.
6
CPU_RST
R/W
0
CPU Reset bit
1 = Internal CPU is held in RESET
0 = Internal CPU is active
This is strictly a CPU reset. Toggling this bit reset the cpu only and will not change any
contents of the I2C registers
5
Reserved
R/W
0
Reserved
4
PAR_EN
R/W
0
SRAM Parity Enable bit:
1 = SRAM Parity Check will be enabled
0 = SRAM Parity Check will be disabled
It is recommended that the Parity function be enable whenever SRAM is being used
3
RAM_EN
R/W
0
SRAM Enable bit
1 = SRAM will be enabled and the internal CPU will run from both SRAM and internal ROM
0 = Internal CPU will run from internal ROM only
This bit needs to be set to a 1 after SRAM programing to enable the utilization of the SRAM
code
2
PAR_SEL
R/W
0
SRAM Parity Select bit: Setting this bit to a 1 in conjunction with the RZ/W bit enables
access to the SRAM Parity bits.
1 = Parity bits read/write is enabled
0 = Parity bits read/write is disabled
1
R/WZ
R/W
0
SRAM Read/Write select bit:
0 = SRAM Write – SRAM data is written with a write to 0x61h
1 = SRAM Read – SRAM data is read with a read from 0x61h
SRAM data can be continuously read/written over I2C until a STOP bit is sent.
0
CLR_PTR
R/W
0
Clear Address Pointer bit:
1 = Resets the memory address pointer
0 = Releases pointer for use
In order to ensure proper programming, this bit should be toggled (0-1-0) to writing or
reading the SRAM or Parity memory.
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SRAM Programming:
Upon power up, it is recommenced that the TPS23881's SRAM be programmed to the latest version of code
available for download through the TI mySecure Software webpage.. All I2C traffic other than those commands
outlined below to program the SRAM shall be deferred until after the SRAM programming sequences below are
complete.
NOTE
For TPS23881 applications choosing not to load SRAM and run from the internal ROM
only, please consult the SRAM Release notes and ROM Advisory documentation available
through the TI mySecure Software webpage.
NOTE
The SRAM programming control must be completed at the lower I2C address (Channels
1-4). Configuring this registers for the upper I2C device address (Channels 5-8) will not
program the SRAM
NOTE
The SRAM programming needs to be delayed at least 50ms from the initial power on
(VPWR and VDD above UVLO) of the device to allow for the device to complete its
internal hardware initialization process
0x60h setup for SRAM Programming: Prior to programming/writing the SRAM, the following bits sequence
needs to be completed in register 0x60h:
7
PROG_SEL
0→1
6
CPU_RST
0→1
5
0
4
PAR_EN
0
3
RAM_EN
0
2
PAR_SEL
0
1
R/WZ
1→0
0
CLR_PTR
0→1→0
The same sequence is required to read the SRAM with the exception that the R/WZ bit needs to be set to “1”.
If the device is in “Safe Mode”, the same sequence as above may be used to reprogram the SRAM.
An I2C write to 0x61h following this sequence actively programs the SRAM program memory starting from the
address set in registers 0x62h and 63h.
SPACE
0x60h setup for SRAM Parity Programming: Following the programming of the SRAM program memory, the
following bits sequence needs to be completed in register 0x60h in order to configure the device to program the
Parity memory:
7
PROG_SEL
0→1
6
CPU_RST
0→1
5
0
4
PAR_EN
0
3
RAM_EN
0
2
PAR_SEL
0→1
1
R/WZ
1→0
0
CLR_PTR
0→1→0
The same sequence is required to read the Parity with the exception that the R/WZ bit needs to be set to “1".
An I2C write to 0x61h following this sequence actively programs the Parity memory starting from the address set
in registers 0x62h and 63h.
110
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0x60h setup to run from SRAM Program Memory: Upon completion of programming, the following bits
sequence needs to be completed in register 0x60h in order to enable the device to run properly out of SRAM:
7
PROG_SEL
1→0
6
CPU_RST
1→0
5
0
4
PAR_EN
0→1
3
RAM_EN
0→1
2
PAR_SEL
1→0
1
R/WZ
0
0
CLR_PTR
0
Within 1ms of the completion of the above sequence, the device will complete a compatibility check on the
SRAM
If the SRAM load is determined to be “Valid”: Register 0x41h will have a value between 0x01h and 0xFEh, and
the device will return to normal operation.
If the SRAM load is determined to be “Invalid”:
• 0x41h will be set to 0xFFh
• The RAM_EN bit will be internally cleared
• The device will operating in “safe mode” until another programming attempt is completed
SPACE
SPACE
9.6.2.71 SRAM START ADDRESS (LSB) Register
COMMAND = 62h with 1 Byte, Read/Write
Figure 120. SRAM START ADDRESS (LSB) Register Format
7
SA_7
R/W-0
6
SA_6
R/W-0
5
SA_5
R/W-0
4
SA_4
R/W-0
3
SA_3
R/W-0
2
SA_2
R/W-0
1
SA_1
R/W-0
0
SA_0
R/W-0
1
SA_9
R/W-0
0
SA_8
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
9.6.2.72 SRAM START ADDRESS (MSB) Register
COMMAND = 63h with 1 Byte, Read/Write
Figure 121. SRAM START ADDRESS (MSB) Register Format
7
SA_15
R/W-0
6
SA_14
R/W-0
5
SA_13
R/W-0
4
SA_12
R/W-0
3
SA_11
R/W-0
2
SA_10
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 68. SRAM START ADDRESS Register Field Descriptions
Bit
15-0
Field
Type
Reset
SA_15- SA_0
R/W
0
Description
SRAM and Parity Programing Start Address bits:
the value entered into these registers sets the start address location for the SRAM or Parity
programming
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10 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
10.1 Application Information
The TPS23881 is an 8-channel, IEEE 802.3bt ready PoE PSE controller and can be used in high port count
semiauto or fully micro-controller managed applications (The MSP430FR5969 micro-controller is recommended
for most applications). Subsequent sections describe detailed design procedures for applications with different
requirements including host control.
The schematic of Figure 122 depicts semiauto mode operation of the TPS23881, providing functionality to power
PoE loads. The TPS23881 can do the following:
1. Performs load detection.
2. Performs classification for type-1 (one finger) through type-4 (five finger) loads.
3. Enables power on with protective foldback current limiting, and Port power policing (PCUT) value.
4. Shuts down in the event of fault loads and shorts.
5. Performs Maintain Power Signature function to insure removal of power if load is disconnected.
6. Undervoltage lock out occurs if VPWR falls below VPUV_F (typical 26.5 V).
Following a power-off command, disconnect or shutdown due to a Start, PCUT or ILIM fault, the port powers down.
Following port power off due to a disconnect, the TPS23881 will immediate restart the detection and
classification cycles if the DETE and CLE bits are set in register 0x14. If the shutdown is due to a start, PCUT or
ILIM fault, the TPS23881 enters into a cool-down period during which any Detect/Class Enable Command for that
port will be delayed. At the end of cool down cycle, one or more detection/class cycles are automatically
restarted if the class and/or detect enable bits are set. If a port is disabled using the power off command, the
DETE and CLE bits will be cleared and these bits will need to be reset over I2C in order for detection and
classification to resume.
10.1.1 Autonomous Operation
Unlike Auto mode, which still requires a host to initialize the TPS23881 operation through a a series of I2C
commands, there is no host or I2C communication required when the TPS23881 in configured in Autonomous
mode.
Connecting a resistor between the AUTO pin and GND based on the table below will enable autonomous mode
and configure all of the ports to the same Power Allocation settings. In the event a PD is connected with a higher
requested class than the autonomous mode configuration, the port will power demote the PD to the selected
autonomous mode configuration power level. The port automatically performs detection and classification (if valid
detection occurs) continuously on all ports. Port power is automatically turned on based on Power Allocation
settings in register 0x29 if a valid classification is measured.
Table 69. AUTO Pin Programming
112
Auto Pin
Autonomous Mode Configuration
Open/Floating
Disabled
124 kΩ
2-pair 15 W
62 kΩ
2-pair 30 W
35.7 kΩ
4-pair 30W
22.6 kΩ
4-pair 45W
15.8 kΩ
4-pair 60W
11 kΩ
4-pair 75W
7.7 kΩ
4-pair 90W
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SPACE
NOTE
A 10 nF capacitor is required in parallel with RAUTO to ensure stability in the Autonomous
mode selection.
10.1.2 Introduction to PoE
Power-over-Ethernet (PoE) is a means of distributing power to Ethernet devices over the Ethernet cable using
either data or spare pairs. PoE eliminates the need for power supplies at the Ethernet device. Common
applications of PoE are security cameras, IP Phones and wireless access points (WAP). The host or mid-span
equipment that supplies power is the power source equipment (PSE). The load at the Ethernet connector is the
powered device (PD). PoE protocol between PSE and PD controlling power to the load is specified by IEEE
802.3bt standard. Transformers are used at Ethernet host ports, mid-spans and hubs, to interface data to the
cable. A DC voltage can be applied to the center tap of the transformer with no effect on the data signals. As in
any power transmission line, a relatively high voltage (approximately 50 V) is used to keep currents low and
minimize the effects of IR drops in the line to preserve power delivery to the load. Standard 2-Pair PoE delivers
approximately 13 W to a type 1 PD, and 25.5 W to a type 2 PD, whereas standard 4-Pair PoE will be capable of
delivering approximately 51 W to a type 3 PD and 71 W to a type 4 PD.
10.1.2.1 2-Pair Versus 4-Pair Power and the New IEEE802.3bt Standard
The IEEE 802.3at-2009 standard previously expanded PoE power delivery from 15.4W (Commonly referred to as
.af or Type-1 PoE) to 30 W (.at or Type-2 PoE) of sourced power from the PSE (Power Sourcing Equipment)
over 2-pairs of ethernet wires (Commonly known as either the Alt-A or Alt-B pair sets). The IEEE 802.3bt
standard further expands power delivery up to 90 W sourced from a PSE by allowing for power delivery over
both the ALT-A and ALT-B pairsets in parallel. Two new PoE equipment "Types" have also been created as part
of the new standard. Type 3 PSE equipment will be capable of sourcing up to 60 W of power over 4-pair or 30 W
over 2-pair while supporting the new MPS requirements. Type 4 PSE equipment will be capable of sourcing up to
90 W of power over 4-pair. The TPS23881 has been designed to be fully configurable to support any of these
configurations.
The Maintain Power Signature (or MPS) requirements have also been updated for the new standard. The
previous version of the standard only required PSEs to maintain power on a port if the PD (Powered Device)
current exceeded 10 mA for at least 60 ms every 300 ms to 400 ms. By decreasing these requirements to 6 ms
every 320 ms to 400 ms, the minimum power requirement to maintain PoE power have been reduced by a factor
of nearly 10.
10.1.3 SRAM Programming
Upon power up, the TPS23881 device can operate from its internal ROM memory or users have the option of
programming the SRAM via I2C.
NOTE
The latest version of TPS23881 firmware may be accessed from the TI mySecure
Software webpage.
All I2C traffic other than those commands outlined below to program the SRAM shall be deferred until after the
SRAM programming sequences below are complete.
For systems that include multiple TPS23881 devices, the 0x7F "global" broadcast I2C address may be used to
programmed all of the devices at the same time.
Refer to the How to Load TPS2388x SRAM Code document on TI.com for more detailed instructions on the
SRAM programing procedure.
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10.2 Typical Application
This typical application shows an eight (2-Pair) port, semiauto mode application using a MSP430 or similar
micro-controller. Operation in any mode requires I2C host support. The TPS23881 provides useful telemetry in
multi-port applications to aid in implementing port power management.
VPWR
VDD
TPS23881
CVPWR
CVDD
VPWR
43 VDD
P3
VPWR
VPWR
17
P2
+
RJ45
&
XFMR
+
CP3
DP3
DP2
FP3
±
FP2
10 DRAIN3
QP3
8
GAT3
9
SEN3
DRAIN2
5
GAT2
7
SEN2
6
RJ45
&
XFMR
CP2
±
QP2
RS2
RS3
11 KSENSB
KSENSA
4
RS1
RS4
13 SEN4
14 GAT4
QP4
SEN1
2
GAT1
1
DRAIN1
3
QP1
P4
P1
12 DRAIN4
±
RJ45
&
XFMR
FP4
CP4
±
FP1
DP1
DP4
RJ45
&
XFMR
CP1
VDD
+
+
Optional
55 SDAO
VPWR
RRST
RSCL
RSDA
AUTO 52
54 SDAI
I2C Host Device
VPWR
RINT
RAUTO
53 SCL
A1 48
44 RESET
A2 49
45 INT
A3 50
56 OSS
A4 51
10nF
VPWR
P7
VPWR
46 DGND
P6
AGND 21
+
RJ45
&
XFMR
+
CP7
DP7
DP6
FP7
±
FP6
38 DRAIN7
DRAIN6
±
33
QP7
RJ45
&
XFMR
CP6
QP7
36 GAT7
GAT6 35
37 SEN7
SEN6 34
RS6
RS7
39
KSENSD
KSENSC
32
RS8
RS5
41 SEN8
QP8
42 GAT8
SEN5
30
GAT5
29
DRAIN5
31
QP5
P8
P5
40 DRAIN8
-
RJ45
&
XFMR
FP8
CP8
±
FP5
DP8
DP5
+
RJ45
&
XFMR
CP5
+
VPWR
VPWR
Figure 122. Eight 2-Pair Port Application
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Typical Application (continued)
This typical application shows a four (4-Pair) port, semiauto mode application using a MSP430 or similar
microcontroller.
VPWR
VDD
TPS23881
CVPWR
CVDD
VPWR
CP3
43 VDD
VPWR
17
DRAIN2
5
GAT2
7
SEN2
6
VPWR
DP3
DP2
FP3
CP2
FP2
10 DRAIN3
QP3
8
GAT3
9
SEN3
QP2
4-Pair
P1
4-Pair
P2
RS2
RS3
+
ALT-A
ALT-A
±
±
11 KSENSB
KSENSA
4
±
±
RJ45
&
XFMR
+
ALT-B
ALT-B
+
+
RS1
RS4
QP4
13 SEN4
SEN1
2
14 GAT4
GAT1
1
DRAIN1
3
12 DRAIN4
QP1
FP4
CP4
RJ45
&
XFMR
FP1
DP1
DP4
CP1
VDD
Optional
55 SDAO
VPWR
RRST
RSCL
RSDA
AUTO
VPWR
52
RINT
54 SDAI
I2C Host Device
RAUTO
53 SCL
A1 48
44 RESET
A2 49
45 INT
A3 50
56 OSS
A4 51
10nF
VPWR
VPWR
46 DGND
DP7
DP6
FP7
38 DRAIN7
DRAIN6
33
QP7
QP7
36 GAT7
GAT6 35
37 SEN7
SEN6 34
4-Pair
P4
RS7
4-Pair
P3
RS6
+
ALT-A
±
ALT-A
39
KSENSD
KSENSC
32
±
ALT-B
ALT-B
+
RS8
RJ45
&
XFMR
RS5
QP8
41 SEN8
SEN5
30
42 GAT8
GAT5
29
DRAIN5
31
40 DRAIN8
FP8
CP8
+
±
±
RJ45
&
XFMR
CP6
FP6
+
CP7
AGND 21
QP5
FP5
DP8
DP5
VPWR
CP5
VPWR
Figure 123. Four 4-Pair Port Application
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Typical Application (continued)
10.2.1 Design Requirements
TPS23881 devices are used in the eight port configuration and are managed by the I2C host device. The I2C
address for TPS23881 is programmed using the A4..A1 pins. When using multiple TPS23881 devices in a
system, each device requires by a unique I2C address. See PIN STATUS Register for more information on how
to program the TPS23881 I2C address.
Figure 122 and Figure 123 show typical application for either all 2-pair or 4-pair ports, but the TPS23881 may
also be configured to support any combination of either 2-pair or 4-pair PSE ports. 4-pair port requires the use of
both Alternative A and Alternative B wire pair sets at the RJ45 terminal, whereas a 2-pair port only requires the
Alternative A pair set to be used.
A MCU is not required to operate the TPS23881 device, but some type of I2C master/host controller device is
required to program the internal SRAM and initialize the basic I2C register configuration of the TPS23881.
It is recommended that the RESET pin be connected to a micro-controller or other external circuitry.
NOTE
The RESET pin must be held low until both VPWR and VDD are above their UVLO
thresholds.
Refer to the TPS23881EVM User's Guide for more detailed information.
10.2.2 Detailed Design Procedure
Refer to the TPS23881EVM User's Guide for more detailed information on component selection and layout
recommendations.
10.2.2.1 Connections on Unused Channels
On unused channels, it is recommended to ground the SENx pin and leave the GATx pin open. DRAINx pins can
be grounded or left open (leaving open may slightly reduce power consumption). Figure 124 shows an example
of an unused PORT2.
DRAIN2
5
GAT2
7
SEN2
6
KSENSA
4
TPS23881
RS1
SEN1
2
GAT1
1
DRAIN1
3
P1
±
FP1
DP1
RJ45
&
XFMR
CP1
+
VPWR
Figure 124. Unused PORT2 Connections
116
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Typical Application (continued)
10.2.2.2 Power Pin Bypass Capacitors
• CVPWR: 0.1 μF, 100 V, X7R ceramic at pin 17 (VPWR)
• CVDD: 0.1 μF, 5 V, X7R ceramic at pin 43 (VDD)
• CAUTO (1): 10 nF, 5 V, X7R ceramic at pin 52 (AUTO) (1)
10.2.2.3 Per Port Components
•
•
CPn: 0.1-μF, 100-V, X7R ceramic between VPWR and PnRSn: Each channel's current sense resistor is a 0.2-Ω. A 1%, 0.25-W resistor in an 0805 SMT package is
recommended. If a 90W Policing (PCUT) threshold is selected, the maximum power dissipation for the resistor
becomes approximately 140 mW.
NOTE
For systems requiring either more accurate system power monitoring or precise Port
Power Policing accuracy, it is recommend that 0.1% RSENSE resistors be used.
•
QPn: The port MOSFET can be a small, inexpensive device with average performance characteristics. BVDSS
should be 100 V minimum. Target a MOSFET RDS(on) at VGS = 10 V of between 50 mΩ and 150 mΩ. The
MOSFET GATE charge (QG) and input capacitance (CISS) should be less than 50 nC and 2000 pF
respectively. The maximum power dissipation for QPn with RDS(on) = 100 mΩ at 640 mA nominal policing
(ICUT) threshold is approximately 45 mW.
NOTE
In addition to the MOSFET RDS(on) and BVDSS characteristics, the power MOSFET SOA
ratings also need to be taken into consideration when selecting these components for your
system design. It is recommended that a MOSFET be chosen with an SOA rating that
exceeds the inrush and operational foldback characteristic curves as shown in Figure 39
and Figure 40. When using the standard current foldback (ALTIRn or ALTFBn = 0)
options, the CSD19538Q3A 100V N-Channel MOSFET is recommended.
•
•
(1)
FPn: The port fuse should be a slow blow type rated for at least 60 VDC and above approximately 2 x PCUT
(max). The cold resistance should be below 200 mΩ to reduce the DC losses. The power dissipation for FPn
with a cold resistance of 180 mΩ at maximum PCUT is approximately 150 mW.
DPnA: The port TVS should be rated for the expected port surge environment. DPnA should have a minimum
reverse standoff voltage of 58 V and a maximum clamping voltage of less than 95 V at the expected peak
surge current
Only required if RAUTO is also connected to the AUTO pin
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Typical Application (continued)
10.2.2.4 System Level Components (not shown in the schematic diagrams)
The system TVS and bulk VPWR capacitance work together to protect the PSE system from surge events which
could cause VPWR to surge above 70 V. The TVS and bulk capacitors should be placed on the PCB such that
all TPS23881 ports are adequately protected.
• TVS: The system TVS should be rated for the expected peak surge power of the system and have a
minimum reverse standoff voltage of 58 V. Together with the VPWR bulk capacitance, the TVS must prevent
the VPWR rail from exceeding 70 V.
• Bulk Capacitor: The system bulk capacitor(s) should be rated for 100 V and can be of aluminum electrolytic
type. Two 47-μF capacitors can be used for each TPS23881 on board.
• Distributed Capacitance:In higher port count systems, it may be necessary to distribute 1-uF, 100-V, X7R
ceramic capacitors across the 54-V power bus. One capacitor per each TPS23881 pair is recommended.
• Digital I/O Pullup Resistors: RESET and A1-A4 are internally pulled up to VDD, while OSS is internally
pulled down, each with a 50-kΩ (typical) resistor. A stronger pull-up/down resistor can be added externally
such as a 10 kΩ, 1%, 0.063 W type in a SMT package. SCL, SDAI, SDAO, and INT require external pull-up
resistors within a range of 1 kΩ to 10 kΩ depending on the total number of devices on the bus .
• Ethernet Data Transformer (per port): The Ethernet data transformer must be rated to operate within the
IEEE802.3bt standard in the presence of the DC port current conditions. The transformer is also chosen to be
compatible with the Ethernet PHY. The transformer may also be integrated into the RJ45 connector and cable
terminations.
• RJ45 Connector (per port): The majority of the RJ45 connector requirements are mechanical in nature and
include tab orientation, housing type (shielded or unshielded), or highly integrated. An integrated RJ45
consists of the Ethernet data transformer and cable terminations at a minimum. The integrated type may also
contain the port TVS and common mode EMI filtering.
• Cable Terminations (per port): The cable terminations typically consist of series resistor (usually 75 Ω) and
capacitor (usually 10 nF) circuits from each data transformer center tap to a common node which is then
bypassed to a chassis ground (or system earth ground) with a high-voltage capacitor (usually 1000 pF to
4700 pF at 2 kV).
118
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Typical Application (continued)
10.2.3 Application Curves
Unless otherwise noted, measurements taken on the TPS23881 EVM and Sifos PSA-3000 PowerSync Analyzer with
PSA3202 test cards. Test conditions are TJ = 25 °C, VVDD = 3.3 V, VVPWR = 54 V, VDGND = VAGND, DGND, KSENSA, KSENSB,
KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn = 0. Positive currents are into pins. RS =
0.200 Ω, to KSENSA (SEN1 or SEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to KSENSD (SEN7 or
SEN8). All voltages are with respect to AGND unless otherwise noted. Operating registers loaded with default values unless
otherwise noted.
DRAINALT-A
DRAINALT-A
GATEALT-A
GATEALT-A
Figure 125. 2-Pair ILIM Foldback and Turn Off
Figure 126. 2-Pair Backoff due to PCut Fault
DRAINALT-B
DRAINALT-A
DRAINALT-B
DRAINALT-A
GATEALT-B
GATEALT-B
GATEALT-A
GATEALT-A
Figure 127. 4-Pair ILIM Foldback and Turn Off
Figure 128. 4-Pair Backoff Due to ILIM Fault
DRAINALT-B
DRAINALT-A
DRAINALT-B
DRAINALT-A
GATEALT-B
GATEALT-B
GATEALT-A
GATEALT-A
Figure 130. 4-Pair Single Signature Class 0-4 Disconnect
Figure 129. 4-Pair Backoff Due to 4PPCut Fault
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Typical Application (continued)
Unless otherwise noted, measurements taken on the TPS23881 EVM and Sifos PSA-3000 PowerSync Analyzer with
PSA3202 test cards. Test conditions are TJ = 25 °C, VVDD = 3.3 V, VVPWR = 54 V, VDGND = VAGND, DGND, KSENSA, KSENSB,
KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn = 0. Positive currents are into pins. RS =
0.200 Ω, to KSENSA (SEN1 or SEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to KSENSD (SEN7 or
SEN8). All voltages are with respect to AGND unless otherwise noted. Operating registers loaded with default values unless
otherwise noted.
DRAINALT-B
DRAINALT-A
DRAINALT-A
GATEALT-B
GATEALT-A
GATEALT-A
Figure 132. 4-Pair Open Circuit Detection Signature
Figure 131. 2-Pair Open Circuit Detection Signature
DRAINALT-B
DRAINALT-B
DRAINALT-A
DRAINALT-A
Figure 133. 4-Pair Low Resistance (11kΩ) Detection
Signature
Figure 134. 4-Pair High Resistance (36kΩ) Detection
Signature
DRAINALT-A
DRAINALT-A
GATEALT-A
GATEALT-A
Figure 135. 2-Pair Semi-Auto Mode Discovery with a Valid
Class 0-3 Load
120
Figure 136. 2-Pair 1-Finger Classification and Turn On
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Typical Application (continued)
Unless otherwise noted, measurements taken on the TPS23881 EVM and Sifos PSA-3000 PowerSync Analyzer with
PSA3202 test cards. Test conditions are TJ = 25 °C, VVDD = 3.3 V, VVPWR = 54 V, VDGND = VAGND, DGND, KSENSA, KSENSB,
KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn = 0. Positive currents are into pins. RS =
0.200 Ω, to KSENSA (SEN1 or SEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to KSENSD (SEN7 or
SEN8). All voltages are with respect to AGND unless otherwise noted. Operating registers loaded with default values unless
otherwise noted.
DRAINALT-B
DRAINALT-A
DRAINALT-A
GATEALT-B
GATEALT-A
GATEALT-A
Figure 138. 4-Pair Semi-Auto Mode Discovery with a Valid
Single Signature Class 0-3 Load
Figure 137. 2-Pair 3-Finger Classification and Turn On
DRAINALT-B
DRAINALT-B
DRAINALT-A
DRAINALT-A
GATEALT-B
GATEALT-B
GATEALT-A
GATEALT-A
Figure 139. 4-Pair Single Signature Discovery and Turn On
from Semi-Auto Mode
Figure 140. 4-Pair Single Signature 1-Finger Classification
and Turn On
DRAINALT-B
DRAINALT-B
DRAINALT-A
DRAINALT-A
GATEALT-B
GATEALT-B
GATEALT-A
GATEALT-A
Figure 141. 4-Pair Single Signature 3-Finger Classification
and Turn On
Figure 142. 4-Pair Single Signature 4-Finger Classification
and Turn On
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Typical Application (continued)
Unless otherwise noted, measurements taken on the TPS23881 EVM and Sifos PSA-3000 PowerSync Analyzer with
PSA3202 test cards. Test conditions are TJ = 25 °C, VVDD = 3.3 V, VVPWR = 54 V, VDGND = VAGND, DGND, KSENSA, KSENSB,
KSENSC and KSENSD connected to AGND, and all outputs are unloaded, 2xFBn = 0. Positive currents are into pins. RS =
0.200 Ω, to KSENSA (SEN1 or SEN2), to KSENSB (SEN3 or SEN4), to KSENSC (SEN5 or SEN6) or to KSENSD (SEN7 or
SEN8). All voltages are with respect to AGND unless otherwise noted. Operating registers loaded with default values unless
otherwise noted.
DRAINALT-B
DRAINALT-B
DRAINALT-A
DRAINALT-A
GATEALT-B
GATEALT-B
GATEALT-A
GATEALT-A
Figure 143. 4-Pair Single Signature 5-Finger Classification
and Turn On
Figure 144. 4-Pair Semi-Auto Mode Discovery with a Valid
Dual Signature Class 4D Load
DRAINALT-B
DRAINALT-B
DRAINALT-A
DRAINALT-A
GATEALT-B
GATEALT-B
GATEALT-A
GATEALT-A
Figure 145. 4-Pair Dual Signature Discovery and Turn On
from Semi-Auto Mode
Figure 146. 4-Pair Dual Signature 1-Finger Classification
and Turn On
DRAINALT-B
DRAINALT-B
DRAINALT-A
DRAINALT-A
GATEALT-B
GATEALT-B
GATEALT-A
GATEALT-A
Figure 147. 4-Pair Dual Signature 3-Finger Classification
and Turn On
122
Figure 148. 4-Pair Dual Signature 4-Finger Classification
and Turn On
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11 Power Supply Recommendations
11.1 VDD
The recommended VDD supply voltage requirement is 3.3 V, ±0.3 V. The TPS23881 requires approximately 6
mA typical and 12 mA maximum from the VDD supply. The VDD supply can be generated from VPWR with a
buck-type regulator (A LM5017 based device is recommended) for a higher port count PSE using multiple
TPS23881 devices operating in semiauto mode. The power supply design must ensure the VDD rail rises
monotonically through the VDD UVLO thresholds without any droop under the UVLO_fall threshold as the loads
are turned on. This is accomplished with proper bulk capacitance across the VDD rail for the expected load
current steps over worst case design corners. Furthermore, the combination of decoupling capacitance and bulk
storage capacitance must hold the VDD rail above the UVLO_fall threshold during any expected transient
outages once power is applied.
11.2 VPWR
Although the supported VPWR supply voltage range is 44 V to 57 V, a power supply with a 50 V minimum output
is required to provide PoE power levels from 30 W up to 60 W over 2-pair and 4-pair, and a 52 V minimum
power supply is required to comply with Type-4 (up to 90W) IEEE requirements. The TPS23881 requires
approximately 10-mA typical and 12-mA maximum from the VPWR supply, but the total output current required
from the VPWR supply depends on the number and type of ports required in the system. The TPS23881 can be
configured to support either 15.5 W, 30 W, 45 W, 60 W, 75W, or 90 W per port and the power limit is set
proportionally at turn on. The port power limit, PCUT, is also programmable to provide even greater system design
flexibility. However, it is generally recommend to size the VPWR supply accordingly to the PoE Type to be
supported. As an example, a 130 W or greater power supply would be recommended for eight type 1 (15.5 W
each) ports, or a 500 W or greater power supply is recommended for eight 4-pair type 3 (60 W) ports, assuming
maximum port and standby currents.
NOTE
In IEEE complaint applications, only 4-Pair configured ports are capable of supporting
power levels greater than 30 W.
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12 Layout
12.1 Layout Guidelines
12.1.1 Kelvin Current Sensing Resistors
Load current in each PSE channel is sensed as the voltage across a low-end current-sense resistor with a value
of 200 mΩ. For more accurate current sensing, kelvin sensing of the low end of the current-sense resistor is
provided through pins KSENSA for channels 1 and 2, KSENSB for channels 3 and 4, KSENSC for channels 5
and 6 and KSENSD for channels 7 and 8.
VPWR
P2
+
DP2
FP2
DRAIN2
5
GAT2
7
SEN2
6
KSENSA
4
RJ45
&
XFMR
CP2
±
QP2
RS2
Note: only two channels shown
TPS23881
RS1
SEN1
2
GAT1
1
DRAIN1
3
P1
±
FP1
DP1
CP1
RJ45
&
XFMR
+
VPWR
Figure 149. Kelvin Current-Sense Connection
KSENSA is shared between SEN1 and SEN2, KSENSB is shared between SEN3 and SEN4, KSENSC is shared
between SEN5 and SEN6, and KSENSD is shared between SEN7 and SEN8. To optimize the accuracy of the
measurement, the PCB layout must be done carefully to minimize impact of PCB trace resistance. Refer to as an
example.
to SENSE1 pin
RS1
Shape Connecting RS1 and
RS2 to KSENSA
KSENSA Route
to TPS23881
RS2
Vias Connecting
Shape to GND Layer
to SENSE2 pin
Figure 150. Kelvin Sense Layout Example
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12.2 Layout Example
QP1
RS8A
KSENSD
KSENSA
QP8
RS1
RS8
RS2
RS7
QP2
RDRN4
QP7
RS2A
RS7A
TPS23881
RS3A
RS6A
QP3
FP3
KSENSB
RS6
RS4
RS5
P3
CP2
RS4A
GND
VPWR
RS3
DP3B
DP2B
QP4
QP6
KSENSC
QP5
RS5A
P2
Note: PCB layout includes footprints for optional parallel RSENSE resistors
Figure 151. Eight Port Layout Example (Top Side)
12.2.1 Component Placement and Routing Guidelines
12.2.1.1 Power Pin Bypass Capacitors
•
•
•
CVPWR: Place close to pin 17 (VPWR) and connect with low inductance traces and vias according to
Figure 151.
CVDD: Place close to pin 43 (VDD) and connect with low inductance traces and vias according to Figure 151
CAUTO (2): Place close to pin 52 (AUTO) and connect with low inductance traces and vias. (2)
12.2.1.2 Per-Port Components
•
•
•
(2)
RSnA / RSnB: Place according to in a manner that facilitates a clean Kelvin connection with KSENSEA/B/C/D.
QPn: Place QPn around the TPS23881 as illustrated in Figure 151. Provide sufficient copper from QPn drain to
FPn.
FPn, CPn, DPnA, DPnB: Place this circuit group near the RJ45 port connector (or port power interface if a
daughter board type of interface is used as illustrated in Figure 151). Connect this circuit group to QPn drain
or GND (TPS23881- AGND) using low inductance traces.
Only required if RAUTO is also connected to the AUTO pin
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13 Device and Documentation Support
13.1 Documentation Support
13.1.1 Related Documentation
For related documentation see the following:
Texas Instruments, TPS23881EVM User's Guide
13.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
13.3 Support Resources
TI E2E™ support forums are an engineer's go-to source for fast, verified answers and design help — straight
from the experts. Search existing answers or ask your own question to get the quick design help you need.
Linked content is provided "AS IS" by the respective contributors. They do not constitute TI specifications and do
not necessarily reflect TI's views; see TI's Terms of Use.
13.4 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
13.5 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
13.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
14 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
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PACKAGE OPTION ADDENDUM
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7-Oct-2019
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
TPS23881ARTQR
ACTIVE
QFN
RTQ
56
2000
Green (RoHS
& no Sb/Br)
CU NIPDAUAG
Level-3-260C-168 HR
-40 to 125
TPS23881A
TPS23881ARTQT
ACTIVE
QFN
RTQ
56
250
Green (RoHS
& no Sb/Br)
CU NIPDAUAG
Level-3-260C-168 HR
-40 to 125
TPS23881A
TPS23881RTQR
ACTIVE
QFN
RTQ
56
2000
Green (RoHS
& no Sb/Br)
CU NIPDAUAG
Level-3-260C-168 HR
-40 to 125
TPS23881
TPS23881RTQT
ACTIVE
QFN
RTQ
56
250
Green (RoHS
& no Sb/Br)
CU NIPDAUAG
Level-3-260C-168 HR
-40 to 125
TPS23881
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
7-Oct-2019
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
7-Oct-2019
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
TPS23881ARTQR
QFN
RTQ
56
TPS23881ARTQT
QFN
RTQ
TPS23881RTQR
QFN
RTQ
TPS23881RTQT
QFN
RTQ
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
2000
330.0
16.4
8.3
8.3
1.1
12.0
16.0
Q2
56
250
180.0
16.4
8.3
8.3
1.1
12.0
16.0
Q2
56
2000
330.0
16.4
8.3
8.3
1.1
12.0
16.0
Q2
56
250
180.0
16.4
8.3
8.3
1.1
12.0
16.0
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
7-Oct-2019
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
TPS23881ARTQR
QFN
RTQ
56
2000
367.0
367.0
38.0
TPS23881ARTQT
QFN
RTQ
56
250
210.0
185.0
35.0
TPS23881RTQR
QFN
RTQ
56
2000
367.0
367.0
38.0
TPS23881RTQT
QFN
RTQ
56
250
210.0
185.0
35.0
Pack Materials-Page 2
GENERIC PACKAGE VIEW
RTQ 56
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
8 x 8, 0.5 mm pitch
Images above are just a representation of the package family, actual package may vary.
Refer to the product data sheet for package details.
4224653/A
www.ti.com
PACKAGE OUTLINE
RTQ0056E
VQFN - 1 mm max height
SCALE 1.500
PLASTIC QUAD FLATPACK - NO LEAD
8.15
7.85
B
A
PIN 1 INDEX AREA
8.15
7.85
1.0
0.8
C
SEATING PLANE
0.05
0.00
0.08 C
2X 6.5
5.7 0.1
EXPOSED
THERMAL PAD
(0.2) TYP
SYMM
28
15
14
29
SYMM
57
2X 6.5
5.7 0.1
1
52X 0.5
PIN 1 ID
42
56
43
56X
0.5
0.3
56X
0.30
0.18
0.1
0.05
C A B
4224191/A 03/2018
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.
www.ti.com
EXAMPLE BOARD LAYOUT
RTQ0056E
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
(5.7)
(2.6) TYP
SEE SOLDER MASK
DETAIL
(1.35) TYP
56X (0.6)
56
43
56X (0.24)
1
42
52X (0.5)
(2.6) TYP
(R0.05) TYP
(1.35) TYP
57
SYMM
(7.8)
(5.7)
( 0.2) TYP
VIA
14
29
28
15
SYMM
(7.8)
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE: 10X
0.07 MIN
ALL AROUND
0.07 MAX
ALL AROUND
METAL UNDER
SOLDER MASK
METAL EDGE
EXPOSED METAL
SOLDER MASK
OPENING
EXPOSED
METAL
NON SOLDER MASK
DEFINED
(PREFERRED)
SOLDER MASK
OPENING
SOLDER MASK DEFINED
SOLDER MASK DETAILS
4224191/A 03/2018
NOTES: (continued)
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature
number SLUA271 (www.ti.com/lit/slua271).
5. Vias are optional depending on application, refer to device data sheet. If any vias are implemented, refer to their locations shown
on this view. It is recommended that vias under paste be filled, plugged or tented.
www.ti.com
EXAMPLE STENCIL DESIGN
RTQ0056E
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
(0.675) TYP
56X (0.6)
(1.35) TYP
43
56
56X (0.24)
1
42
52X (0.5)
(1.35) TYP
(R0.05) TYP
57
(0.675) TYP
(7.8)
SYMM
16X (1.15)
14
29
15
SYMM
28
16X (1.15)
(7.8)
SOLDER PASTE EXAMPLE
BASED ON 0.125 MM THICK STENCIL
SCALE: 10X
EXPOSED PAD 57
65% PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE
4224191/A 03/2018
NOTES: (continued)
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
www.ti.com
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IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD
PARTY INTELLECTUAL PROPERTY RIGHTS.
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable
standards, and any other safety, security, or other requirements. These resources are subject to change without notice. TI grants you
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Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2019, Texas Instruments Incorporated
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