DEMO MANUAL DC1899A LTC4228-1/LTC4228-2 Dual Ideal Diode and Hot Swap Controller

DEMO MANUAL DC1899A LTC4228-1/LTC4228-2 Dual Ideal Diode and Hot Swap Controller
DEMO MANUAL DC1899A
LTC4228-1/LTC4228-2
Dual Ideal Diode and
Hot Swap Controller
DESCRIPTION
Demonstration circuit 1899A controls two independent
power rail circuits each with Hot Swap™ and ideal diode
functionality provided by the LTC4228-1/LTC4228-2 dual
ideal diode and Hot Swap controller.
DC1899A facilitates evaluation of LTC4228 performance
in different operation modes such as supply ramp-up,
power supply switchover, steady state, and overcurrent
faults. Power supply switchover mode can be realized as
either an ideal diode or as a prioritizer.
Each DC1899A circuit is assembled to operate with a
12V supply and 9A maximum current load. The main
components of the board are the LTC4228 controller, two
MOSFETs operating as ideal diodes, two MOSFETs operating as Hot Swap devices, two current sense resistors, two
jumpers for independently enabling each rail, six LEDs to
PERFORMANCE SUMMARY
SYMBOL
PARAMETER
VIN
Input Supply Range
VINTVCC(UVL)
Internal VCC Undervoltage Lockout
indicate status, power good and fault conditions separately
for each channel, and input voltage snubbers. There are
pads for optional RC circuits for each Hot Swap MOSFET
gate in order to adjust output voltage slew rate. In addition
to this there are jumpers allowing monitoring of supply
undervoltage conditions at either IN or SENSE+ pins.
The standard configuration (as DC1899A populated by
default) places the ideal diode MOSFET ahead of the Hot
Swap MOSFET. The board also has pads for an alternative
configuration with the Hot Swap MOSFET located ahead
of the ideal diode MOSFET.
Design files for this circuit board are available at
http://www.linear.com/demo
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Specifications are at TA = 25°C
CONDITIONS
MIN
TYP
2.9
INTVCC Rising
MAX
18
UNITS
V
2.1
2.2
2.3
V
VINTVCC(HYST) Internal VCC Undervoltage Lockout Hysteresis
Ideal Diode Control
30
60
90
mV
ΔVFWD(REG)
Forward Regulation Voltage (VIN – VOUT)
10
25
40
mV
ΔVDGATE
External N-Channel Gate Drive
(VDGATE – VIN)
ΔVFWD = 0.1V
IN < 7V
IN = 7V to 18V
5
10
7
12
14
14
V
V
ICPO(UP)
CPO Pull-Up Current
CPO = IN = 2.9V
CPO = IN = 18V
–60
–50
–95
–85
–120
–110
μA
μA
IDGATE(FPU)
DGATE Fast Pull-Up Current
ΔVFWD = 0.2V, ΔVDGATE = 0V, CPO = 17V
–1.5
A
IDGATE(FPD)
DGATEn Fast Pull-Down Current
ΔVFWD = –0.2V, ΔVDGATE = 5V
1.5
A
Hot Swap Control
ΔVSENSE(CB)
Circuit Breaker Trip Sense Voltage
(VSENSEEn+ – VSENSEEn–)
47.5
50
52.5
mV
ΔVSENSE(ACL)
Active Current Limit Sense Voltage
(VSENSEEn+ – VSENSEEn–)
55
65
75
mV
IHGATE(UP)
External N-Channel Gate Pull-Up Current
Gate Drive On, HGATE = 0V
–7
–10
–13
μA
IHGATE(DN)
External N-Channel Gate Pull-Down Current
Gate Drive Off, OUT = 12V, HGATE = OUT + 5V
150
300
500
μA
IHGATE(FPD)
External N-Channel Gate Fast Pull-Down Current
Fast Turn-Off, OUT = 12V, HGATE = OUT + 5V
100
200
300
mA
dc1899af
1
DEMO MANUAL DC1899A
PERFORMANCE SUMMARY
SYMBOL
PARAMETER
Specifications are at TA = 25°C
CONDITIONS
MIN
TYP
MAX
UNITS
Input/Output Pin
VON(TH)
ONn On Pin Threshold Voltage
ON Rising
1.21
1.235
1.26
V
VON(RESET)
ONn Pin Fault Reset Threshold Voltage
ON Falling
0.55
0.6
0.63
V
VEN(TH)
EN Pin Threshold Voltage
EN Rising
1.185
1.235
1.284
V
VTMR(TH)
TMRn Pin Threshold Voltage
TMR Rising
TMR Falling
1.198
0.15
1.235
0.2
1.272
0.25
V
V
ITMR(UP)
TMRn Pin Pull-Up Current
TMR = 1V, In Fault Mode
–75
–100
–125
μA
ITMR(DN)
TMRn Pin Pull-Down Current
TMR = 2V, No Faults
ITMR(RATIO)
TMRn Current Ratio ITMR(DN)/ITMR(UP)
1.4
2
2.6
μA
1.4
2
2.7
%
OPERATING PRINCINPLES
The LTC4228 functions as an ideal diode with inrush
current limiting and overcurrent protection by controlling
two external back-to-back N-channel MOSFETs in a power
path. The LTC4228 has two ideal diode and two Hot Swap
controllers. Each ideal diode MOSFET is intended to operate with a defined Hot Swap MOSFET, because they are
tied by common on/off control, and ideal diode controller
sense voltage includes both MOSFETs and sense resistor
voltage drop. Therefore, LTC4228 provides independent
control for the two input supplies.
The LTC4228 gate drive amplifiers monitor the voltage
between the INn and OUTn pins and drive the DGATEn
pins. The amplifier quickly pulls up the DGATE pin, turning
on the MOSFET (Q1 or Q3), for ideal diode control when
it senses a large forward voltage drop. Pulling the ON pin
high and EN pins low initiates a 100ms debounce timing
cycle. After this timing cycle, a 10μA current source from
the charge pump ramps up the HGATEn pin. When the Hot
Swap MOSFET (Q2 or Q4) turns on, the inrush current
is limited to a set level set by an external sense resistor
placed between IN and SENSE pins.
An active current limit amplifier servos the gate of the Hot
Swap MOSFET to 65mV across the current sense resistor.
Inrush current can be further reduced, if desired, by adding a capacitor from HGATE to GND. When the MOSFET’s
gate overdrive (HGATE to OUT voltage) exceeds 4.2V, the
PWRGD pin pulls low. When both MOSFETs (Q1 and Q2 or
Q3 and Q4) are turned on, the gate drive amplifier controls
DGATE to servo the forward voltage drop (VIN – VOUT)
across the sense resistor and the back-to-back MOSFETs
to 25mV. If the load current causes more than 25mV of
voltage drop, the gate voltage rises to enhance the MOSFET
used for ideal diode control. For large output currents the
MOSFET’s gate is driven fully on and the voltage drop is
equal to the sum of the ILOAD • RDS(ON) of the two MOSFETs in series.
In the case of an input supply short-circuit when the
MOSFETs are conducting, a large reverse current starts
flowing from the load towards the input. The gate drive
amplifier detects this failure condition as soon as it appears and turns off the ideal diode MOSFET by pulling
down the DGATE pin.
dc1899af
2
DEMO MANUAL DC1899A
QUICK START PROCEDURE
Demonstration circuit 1899A can be easily set up to evaluate
the performance of the LTC4228-1/LTC4228-2. Refer to
the Figure 1 for proper measurement equipment setup and
follow the procedure below. The DC1899A test includes
independent tests of the LTC4228 Hot Swap functionality,
ideal diode functionality and two power rails prioritizer
functionality with the channel 1 highest priority.
HOT SWAP FUNCTIONALITY TEST
This test is identical for each 12V rail and is performed
in the three steps by the measuring of the transient’s
parameters in the different operation modes.
Install the jumpers in the following positions:
JP4, RON1_SEL and JP5, RON2_SEL in position OFF;
JP1, EN1_SEL and JP2, EN2_SEL in position LOW.
RL1
CL1
PSU
SW1
RL2
SW2
CL2
PSU
SW3
SW4
Figure 1. Measurement Equipment Setup for Hot Swap Functionality Test
dc1899af
3
DEMO MANUAL DC1899A
QUICK START PROCEDURE
No-Load Rampup
Current Limit
Connect a 12V power supply to the board input turrets
IN1 (IN2) and GND. Do not load the output. Place current
probe on the 12V supply and voltage probes on the OUT1
(OUT2) turret. Provide ON1 (ON2) signal at the ON1 (ON2)
pin by moving the RON1_SEL (RON2_SEL) jumper from
OFF position to the 12V position. Observe the transient. The
output voltage rise time should be in the range of 12ms
to 29ms. PWRGD1 (PWRGD2) green LED should be lit.
Turn off the rail using the RON1_SEL (RON2_SEL) jumper.
Initially adjust an electronic resistive load to 10Ω to 12Ω
and connect it to the OUT1 (OUT2) turret and GND. Turn
on the rail and slowly increase load current up to the
circuit breaker threshold level. The current limit range
should be between 9A and 12.3A. Turn off the rail using
the RON1_SEL (RON2_SEL) jumper.
VOUT
INPUT CURRENT
dn1899a F02
Figure 2. Turn-On Output Transient Test
CURRENT LIMIT AT 10A
CURRENT 2A/DIV
OUTPUT VOLTAGE
DROPPING DUE
TO SHUTDOWN
dn1899a F03
Figure 3. Current Limiting Test
dc1899af
4
DEMO MANUAL DC1899A
QUICK START PROCEDURE
Power-Up into Output Short
Short the output to ground with a wire. Place the current
probe on this wire. Turn on the rail and record the current
shape. The maximum current should be in the 11.6A to
16.9A range. The LTC4228-1 latches off after overcurrent
condition, but the LTC4228-2 automatically retries after
200ms to 450ms.
IDEAL DIODE FUNCTIONALITY TEST
Use an individual 12V power supply for each rail; connect
the two outputs together at a common load. Adjust each
input voltage to 12V with maximum possible accuracy.
In this test, both rails are active and small variations in
the input voltage will force one channel off and the other
channel on. Place a voltmeter between IN1 and IN2 turrets
to measure the difference between two input voltages.
Activate both rails and keep a load around 1A to 3A. Adjust the input voltage level of one supply such that IN1 is
40mV more positive than IN2. Verify that only channel 1
is drawing current. Repeat this test with IN1 at –40mV
with respect to IN2. In this case channel only channel 2
is drawing current.
PRIORITIZER FUNCTIONALITY TEST
The DC1899A is assembled with components to implement
a power prioritizer with channel 1 having the higher priority.
Place JP7 PPR_SEL (power priority select) jumper in
position ON2 and JP5 RON2_SEL (ON2 select) in position OFF.
Apply independent supply voltages (12V) to both inputs.
Channel 1 will be connected to load. Reduce channel 1
input voltage until it reaches an undervoltage condition
and D6 (PWRGD2) lights. At the same time channel 2
power supply will deliver power to the load.
CURRENT PROFILE DURING
SHORT-CIRCUIT TURN-ON
dn1899a F04
Figure 4. Short-Circuit Test (2A/Div)
dc1899af
5
DEMO MANUAL DC1899A
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
7
C1, C2, C3, C8, C9, C11, C14
CAP., X7R, 0.1μF, 50V, 0603
AVX, 06035C104KAT
2
2
C4, C5
CAP., X7R, 47nF, 50V, 0603
AVX, 06035C473KAT
3
2
C6, C7
CAP., X7R, 15nF, 50V, 0603
AVX, 06035C153KAT
4
0
C10, C12, C13, C15
CAP., ALUMINUM, 100μF 50V, OPT
SANYO, 50CE100BS
5
2
D1, D2
DIODE, VOLTAGE SUPP. 19V 5%, SMA-DIODE
VISHAY, SMAJ17A-E3
6
4
D3, D5, D6, D8
LED, SMT GREEN, J TYPE, LED-LN1351C-GREEN
PANASONIC, LN1351C-TR
7
2
D4, D7
LED, SMT RED, GW TYPE, LED-LN1261C-RED
PANASONIC, LN1261C-TR
8
1
D9
DIODE, SWITCHING, SOD80
VISHAY, LS4148-GS18
9
0
D10, D11, D12, D13
DIODE, CMHZ4706, SOD123
OPT
10
8
E1, E2, E3, E4, E5, E6, E7, E8
TP, 0.094"
MILL-MAX, 2501-2-00-80-00-00-07-0
11
12
E9, E10, E11, E13-E16, E18-E22
TP, 0.064"
MILL-MAX, 2308-2-00-80-00-00-07-0
12
5
JP1, JP2, JP3, JP6, JP7
JMP, HD1X3, 0.079CC
SAMTEC, TMM-103-02-L-S
13
2
JP4, JP5
JMP, HD2X4, 0.079CC
SAMTEC, TMM-104-02-L-D
14
8
J1, J2, J3, J4, J5, J6, J7, J8
JACK, BANANA
KEYSTONE, 575-4
15
4
Q1, Q2, Q3, Q4
MOSFET, N-CH, 30-V, SO8-POWERPAK
VISHAY, SiR158DP
16
0
Q5, Q6, Q7, Q8
MOSFET, N-CH, 30-V, SiR158DP, SO8-POWERPAK
OPT
17
2
RS1, RS2
RES., CHIP, 0.005, 1/2W, 1%, 2010
VISHAY, WSL20105L000FEA
18
0
RS3, RS4
RES., CHIP, 0.005, 1/2W, 1%, 2010, OPT
VISHAY, WSL20105L000FEA
19
4
R1, R3, R19, R20
RES., CHIP, 10Ω, 1%, 0603
VISHAY, CRCW060310R0FKEA
20
2
R2, R4
RES., CHIP, 47Ω, 1%, 0603
VISHAY, CRCW060347R0FKEA
21
6
R5, R6, R7, R8, R9, R10
RES., CHIP, 3k, 1%, 0805
VISHAY, CRCW08053K00FKEA
22
2
R11, R15
RES., CHIP, 20k, 1%, 0603
VISHAY, CRCW0060320K0FKEA
23
2
R12, R16
RES., CHIP, 137k, 1%, 0603
VISHAY, CRCW0603137KFKEA
24
2
R13, R17
RES., CHIP, 49.9k, 1%, 0603
VISHAY, CRCW060349K9FKEA
25
2
R14, R18
RES., CHIP, 28k, 1%, 0603
VISHAY, CRCW0060328K0FKEA
26
0
R21, R25
RES., CHIP, 10Ω, 0603
OPT
27
0
R22, R26
RES., CHIP, 0Ω, 0603
OPT
28
1
R23
RES., CHIP, 470Ω, 1%, 0603
VISHAY, CRCW0603470RFKEA
29
1
R24
RES., CHIP, 41.2k, 1%, 0603
VISHAY, CRCW0060341K2FKEA
I.C. LTC4228IUFD-1, QFN28UFD
LINEAR TECH., LTC4228IUFD-1
I.C. LTC4228IUFD-2, QFN28UFD
LINEAR TECH., LTC4228IUFD-2
DC1899A-A Assembly
2
1
U1
DC1899A-A Assembly
2
1
U1
dc1899af
6
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
A
B
C
J5
E5
J7
E7
E6
E18
GND
GND
E8
J8
ON2
ON1
VIN2
VS2+
5
JP5
HD2X4-079
RON2_SEL
1
2
3
4
5
6
7
8
JP4
HD2X4-079
RON1_SEL
1
2
3
4
5
6
7
8
C11
0.1uF
50V
R19
10
12V
5V
3.3V
OFF
R16
137k
1%
D2
SMAJ17A
C14
0.1uF
50V
R20
10
R17
49.9k
1%
HG1
DG1
DG2
HG2
R18
28k
1%
C9
0.1uF
50V
R12
137k
1%
R15
20K
1%
R13
49.9k
1%
C8
0.1uF
50V
R14
28k
1%
R11
20K
1%
12V
5V
3.3V
OFF
THICK TRACE WIDTH > 500 MIL
SENSE2+ IN2
100uF
50V
OPT
IN2
+ C13
JP6
VON2_SEL
1
2
3
E10
E11
E9
D1
SMAJ17A
THICK TRACE WIDTH > 500 MIL
SENSE1+ IN1
100uF
50V
OPT
+ C10
IN1
VON1_SEL
1
2
3
VIN1
JP3
VS1+
2.9V - 18V
IN2
IN2
ON2
GND
PROBE GND
ON1
GND
GND
J6
2.9V - 18V
IN1
IN1
50V
C1
0.1uF
4
ON1
INTVCC
ON2
50V
C3
0.1uF
16
29
5 EP
GND
21
4
50V
Q3
SiR158DP
INTVCC
C2
0.1uF
Q1
SiR158DP
SENSE1+
R22
0
OPT
DG1
1
SENSE2+
RS2
0.005
0.5W
2010
2010 RS4 OPT
0.5W 0.005
R26
0
OPT
*
QFN28UFD-4X5
U1
RS1
0.005
0.5W
2010
2010 RS3 OPT
0.5W 0.005
HG1
D
4
IN1
CPO2
10
2
1
2
27
CPO1
3
SENSE1+
DGATE1
2
SENSE1+
28
IN1
IN2
6
IN2
DGATE2
9
DG2
SENSE2+
SENSE2+ 7
Q5
SiR158DP
OPT
DG2
HG2
Q7
SiR158DP
OPT
Q4
SiR158DP
TMR2
PWRGD2
FAULT2
STATUS2
EN2
EN1
STATUS1
FAULT1
PWRGD1
TMR1
R1
10
Q2
SiR158DP
HG1
DG1
OUT1
24
SENSE11
SENSE2- 8
OUT1
25
SENSE1SENSE2-
HGATE1
HGATE2
12
HG2
OUT2
13
OUT2
1
C7
15nF
50V
R3
10
C5
47nF 16V
C4
47nF 16V
50V
C6
15nF
R4
47
18
14
15
11
17
20
26
22
23
19
R2
47
D10
CMHZ4706
OPT
R21
10
OPT
D12
CMHZ4706
OPT
R25
10
OPT
3
3
D13
CMHZ4706
OPT
R8
3K
0805
D6
LN1351C
GREEN
E1
OUT1
PPR_SEL
ON2
GND
GND
OUT1
ADJ., 9A
E21
E22
E20
E19
E15
E16
E4
J4
J3
E3
ON2
GND
GND
OUT2
ADJ., 9A
OUT2
PWRGD2
FAULT2
STATUS2
STATUS1
FAULT1
PWRGD1
OFF
JP7
HD1X3-079
3
2
1
E2
J2
J1
CUSTOMER NOTICE
C15 +
100uF
50V
OPT
OUT2
D9
LS4148
R23
470
R24
41.2k
INTVCC
C12 +
100uF
50V
OPT
OUT1
2
E14
E13
JP2
2
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
EN2
EN1
__
ECO
1
REV
1
1ST PROTOTYPE
DESCRIPTION
VLADIMIR O.
APPROVED
REVISION HISTORY
*
U1
LTC Confidential-For Customer Use Only
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
TECHNOLOGY Fax: (408)434-0507
LTC4228IUFD-1
LTC4228IUFD-2
DATE
10-25-11
DATE:
B
SIZE
LTC4228IUFD-1/-2
1
DEMO CIRCUIT 1899A
10/25/2011, 04:28 PM
IC NO.
SHEET 1
OF 1
1
REV.
DUAL IDEAL DIODE AND HOT SWAP CONTROLLER
TITLE: SCHEMATIC
-A
-B
ASSY
1. ALL RESISTORS ARE IN OHMS, 0603.
ALL CAPACITORS ARE IN MICROFARADS, 0603.
NOTE: UNLESS OTHERWISE SPECIFIED
EN2_SEL
EXT
LOW
JP1
EN1_SEL
EXT
LOW
APPROVALS
3
2
1
3
2
1
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
PCB DES.
KIM T.
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APP ENG. VLADIMIR O.
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
SENSE2+
R10
3K
0805
D8
LN1351C
GREEN
D5
LN1351C
GREEN
R7
3K
0805
SENSE1+
Q8
SiR158DP
OPT
R9
3K
0805
D7
LN1261C
RED
D4
LN1261C
RED
R6
3K
0805
R5
3K
0805
D3
LN1351C
GREEN
Q6
SiR158DP
OPT
D11
CMHZ4706
OPT
1
2
2
1
2
1
2
1
2
2
1
1
2
2
1
1
2
2
1
2
1
5
A
B
C
D
DEMO MANUAL DC1899A
SCHEMATIC DIAGRAM
dc1899af
7
DEMO MANUAL DC1899A
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims
arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
dc1899af
8
Linear Technology Corporation
LT 0812 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2012
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