Texas Instruments | 11.3Gbps Modulator Driver | Datasheet | Texas Instruments 11.3Gbps Modulator Driver Datasheet

Texas Instruments 11.3Gbps Modulator Driver Datasheet
ONET1141L
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SLLSEB7 – MAY 2012
11.3 Gbps Modulator Driver
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FEATURES
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•
•
•
•
•
•
•
Digitally Selectable Output Amplitude up to
2.0VPP Single-Ended
Digitally Selectable Bias Current up to 145mA
Source
2-wire Digital Interface with Integrated DACs
and ADC for Control and Diagnostic
Management
Automatic Power Control (APC) Loop
Adjustable Rise and Fall Times
Programmable Input Equalizer
Cross-Point Control
Selectable Monitor PD Current Range and
Polarity
•
•
•
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Includes Laser Safety Features
Single 3.3V Supply
–40°C to 100°C Operation
Surface Mount Small Footprint 4mm × 4mm 24
Pin RoHS Compliant QFN Package
APPLICATIONS
•
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10 Gigabit Ethernet Optical Transmitters
SONET OC-192/SDH STM-64 Optical
Transmitters
10G-EPON and XG-PON
SFP+ and XFP Transceiver Modules
XENPAK, XPAK, X2 and 300-pin MSA
Transponder Modules
DESCRIPTION
The ONET1141L is a high-speed, 3.3V electroabsorption modulator driver designed to bias and modulate an
electroabsorptive modulated laser (EML) at data rates from 1 Gbps up to 11.3 Gbps.
The device provides a two-wire serial interface which allows digital control of the modulation and bias currents,
eliminating the need for external components. Output waveform control, in the form of cross-point adjustment
and rise and fall time adjustment are available to improve the optical eye mask margin. An optional input
equalizer can be used for equalization of up to 150mm (6”) of microstrip or stripline transmission line on FR4
printed circuit boards. The device contains internal analog to digital and digital to analog converters to eliminate
the need for special purpose microcontrollers.
The ONET1141L includes an integrated automatic power control (APC) loop which compensates for variations in
laser average optical power over voltage and temperature and circuitry to support laser safety and transceiver
management systems.
The modulator driver is characterized for operation from –40°C to 100°C case temperatures and is available in a
small footprint 4mm × 4mm 24 pin RoHS compliant QFN package.
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2012, Texas Instruments Incorporated
ONET1141L
SLLSEB7 – MAY 2012
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These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
BLOCK DIAGRAM
A simplified block diagram of the ONET1141L is shown in Figure 1. The modulator driver consists of an input
equalizer with selectable bypass, a limiter, an output driver, DC offset cancellation with cross point control,
power-on reset circuitry, a 2-wire serial interface including a control logic block, a modulation current generator, a
bias current generator with automatic power control loop, an analog to digital converter and an analog reference
block.
VCCO
Crosspoint
Adjust
To all Blocks Except Output Driver
VCC
DC Offset Cancellation
60Ω
60Ω
OUT+
Equalizer
100Ω
OUT-
Amplifier
Limiter
+
DIN+
DIN-
+
Bypass
Mod.
Current
Generator
VCC
Adjustable
Boost
10kΩ
10kΩ
10kΩ
8 Bit Register
8 Bit Register
SDA
SDA
SCK
SCK
DIS
DIS
Settings
Settings
10 Bit Register
IMOD
10 Bit Register
IBIAS
8 Bit Register
8 Bit Register
5 Bit Register
8 Bit Register
3 Bit Register
Equalizer
Crosspoint
Crosspoint Settings
Limiter Current
Monitor Settings
8 Bit Register
8 Bit Register
Bias Current Fault
8 Bit Register
ADC Settings
ADR1
ADR1
ADR2
2-Wire Interface & Control Logic
MONB
MONP
Analog to
Digital
Conversion
PD Current Fault
ADR0
10 Bit Register
BIAS
Bias
Current MONB
Generator/ MONP
Monitor &
FLT
APC
Crosspoint Adjust
PD
COMP
BIAS
MONB
MONP
FLT
PD
COMP
Band-Gap, Analog References,
Power supply Monitor &
Temperature Sensor
ADC
Power-On
Reset
PSM
RZTC
TS
RZTC
Figure 1. Simplified Block Diagram of the ONET1141L
PACKAGE
The ONET1141L is packaged in a small footprint 4mm X 4mm 24 pin RoHS compliant QFN package with a lead
pitch of 0.5mm. The pin out is shown below.
2
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VCCO
GND
OUT-
GND
OUT+
VCCO
24 PIN QFN PACKAGE, 4mm x 4mm
(TOP VIEW)
24 23 22 21 20 19
PD 1
18 BIAS
17 GND
ADR0 2
ONET1141L
1101L
ONET
ADR1 3
16 VCC
24 Lead QFN
24 Lead QFN
“ RGE”
DIS 4
15 COMP
13 MONB
9 10 11 12
RZTC
8
GND
7
DIN+
DIN -
SDA 6
GND
14 MONP
FLT
SCK 5
PIN FUNCTIONS
NO.
PIN
NAME
TYPE
DESCRIPTION
1
PD
Analog
Photodiode input. Pin can source or sink current dependent on register setting.
2
ADR0
Digital-in
2-wire interface address programming pin. Leave this pad open for a default address of 0001000.
Pulling the pin to VCC changes the 1st address bit to a 1 (address = 0001001)
3
ADR1
Digital-in
2-wire interface address programming pin. Leave this pad open for a default address of 0001000.
Pulling the pin to VCC changes the 2nd address bit to a 1 (address = 0001010)
4
DIS
Digital-in
Disables both bias and modulation currents when set to high state. Includes a 10kΩ or 40kΩ pull-up
resistor to VCC. Toggle to reset a fault condition.
5
SCK
Digital-in
2-wire interface serial clock input. Includes a 10kΩ or 40kΩ pull-up resistor to VCC.
6
SDA
Digital-in/out
2-wire interface serial data input/output. Includes a 10kΩ or 40kΩ pull-up resistor to VCC.
7
FLT
Digital-out
Fault detection flag. High level indicates that a fault has occurred. Open drain output. Requires an
external 4.7kΩ to 10kΩ pull-up resistor to VCC for proper operation.
Supply
Circuit ground. Exposed die pad (EP) must be grounded.
8, 11, 17, GND
20, 23, EP
9
DIN+
Analog-in
Non-inverted data input. On-chip differentially 100Ω terminated to DIN–. Must be AC coupled.
10
DIN–
Analog-in
Inverted data input. On-chip differentially 100Ω terminated to DIN+. Must be AC coupled.
12
RZTC
Analog
Connect external zero TC 28.7kΩ resistor to ground (GND). Used to generate a defined zero TC
reference current for internal DACs.
13
MONB
Analog-out
Bias current monitor. Sources a 1% replica of the bias current. Connect an external resistor to
ground (GND) to use the analog monitor (DMONB = 0). If the voltage at this pin exceeds 1.16V a
fault is triggered. Typically choose a resistor to give MONB voltage of 0.8V at the maximum desired
bias current. If the digital monitor function is used (DMONB = 1) the resistor must be removed.
14
MONP
Analog-out
Photodiode current monitor. Sources a 12.5% replica of the photodiode current when PDRNG = 1X,
a 25% replica when PDRNG = 01 and a 50% replica when PDRNG = 00. Connect an external
resistor (5kΩ typical) to ground (GND) to use the analog monitor (DMONP = 0). If the voltage at this
pin exceeds 1.16V a fault is triggered when MONPFLT = 1. If the digital monitor function is used
(DMONP = 1) the resistor must be removed.
15
COMP
Analog
Compensation pin used to control the bandwidth of the APC loop. Connect a 0.01µF capacitor to
ground.
16
VCC
Supply
3.3V ± 10% supply voltage.
18
BIAS
Analog
Sinks or sources the bias current for the laser in both APC and open loop modes.
19, 24
VCCO
Supply
3.3V ± 10% supply voltage for the output stage.
21
OUT–
CML-out
Inverted data output.
22
OUT+
CML-out
Non-inverted data output.
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ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted)
(1)
VALUE
UNIT
MIN
MAX
VCC
Supply voltage (2)
–0.3
4.0
V
VADR0, VADR1, VDIS, VRZTC,
VSCK, VSDA, VDIN+, VDIN-, VFLT,
VMONB, VMONP, VCOMP, VPD,
VBIAS, VOUT+, VOUT-
Voltage at ADR0, ADR1, DIS, RZTC, SCK, SDA, DIN+, DIN–, FLT, MONB,
MONP, COMP, PD, BIAS, OUT+, OUT– (2)
–0.3
4.0
V
IDIN-, IDIN+
Maximum current at input pins
25
mA
IOUT+, IOUT–
Maximum current at output pins
120
mA
IBIAS-MAX
Maximum bias current
180
ESD
ESD rating at all pins
TJ,max
Maximum junction temperature
TSTG
Storage temperature range
TC
Case temperature
(1)
(2)
2
mA
kV (HBM)
125
°C
–65
150
°C
–40
110
°C
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating
conditions” is not implied. Exposure to absolute–maximum–rated conditions for extended periods may affect device reliability.
All voltage values are with respect to network ground terminal.
RECOMMENDED OPERATING CONDITIONS
over operating free-air temperature range (unless otherwise noted)
VCC
Supply voltage
VIH
Digital input high voltage
DIS, SCK, SDA
VIL
Digital input low voltage
DIS, SCK, SDA
Photodiode current range
RRZTC
Zero TC resistor value (1)
MIN
TYP
MAX
UNIT
2.97
3.3
3.63
V
2.0
V
0.8
Control bit PDRNG = 1X,step size = 3 µA
3080
Control bit PDRNG = 01,step size = 1.5 µA
1540
Control bit PDRNG = 00,step size = 0.75 µA
770
28.7
V
µA
1.16V bandgap bias acrossresistor, E96, 1% accuracy
28.4
EQENA = 1
160
1000
29
EQENA = 0
400
1000
kΩ
vIN
Differential input voltage swing
tR-IN
Input rise time
20%–80%
30
55
tF-IN
Input fall time
20%–80%
30
55
ps
TC
Temperature at thermal pad
100
°C
(1)
4
-40
mVp-p
ps
Changing the value will alter the DAC ranges.
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DC ELECTRICAL CHARACTERISTICS
Over recommended operating conditions, with 50Ω output load, open loop operation, VOUT = 2.0Vpp, IBIAS = 80 mA, and RRZTC
= 28.7kΩ unless otherwise noted. Typical operating condition is at VCC =3.3V and TA = 25°C
PARAMETER
VCC
CONDITION
MIN
TYP
MAX
UNIT
2.97
3.3
3.63
V
VOUT = 2.0Vpp, IBIAS = 0mA, EQENA = 0
143
170
VOUT = 2.0Vpp, IBIAS = 0mA, EQENA = 1
151
182
Output off (DIS = HIGH), VOUT = 2.0Vpp,
IBIAS = 80 mA, EQENA = 0
40
Supply voltage
IVCC
Supply current
mA
RIN
Data input resistance
Differential between DIN+ / DIN–
82
100
118
Ω
ROUT
Output resistance
Single-ended at OUT+ or OUT–
50
60
70
Ω
Digital input current
SCK, SDA, pull up to VCC
2
360
470
µA
Digital input current
DIS, pull up to VCC
2
360
470
µA
VOH
Digital output high voltage
FLT, pull-up to VCC, ISOURCE = 50 µA
VOL
Digital output low voltage
FLT, pull-up to VCC, ISINK = 350 µA
IBIAS-MIN
Minimum bias current
See
IBIAS-MAX
IBIAS-DIS
Maximum bias current
2.4
V
0.4
(1)
5
Source. BIASPOL = 0, DAC set to maximum, open
and closed loop
Sink. BIASPOL = 1, DAC set to maximum, open and
closed loop
145
160
93
105
mA
Bias current during disable
100
Average power stability
APC loop enabled
Bias pin compliance voltage
Source. BIASPOL = 0
±0.5
V
VCC–0.9
Temperature sensor accuracy
With 1-point external mid scale calibration
Photodiode reverse bias
voltage
APC active, IPD = max
Photodiode fault current level
Photodiode current monitor
ratio
Percent of target IPD
1.3
(2)
°C
2.3
V
IMONP / IPD with control bit PDRNG = 1X
10%
12.5%
15%
IMONP / IPD with control bit PDRNG = 01
20%
25%
30%
IMONP / IPD with control bit PDRNG = 00
40%
50%
60%
With external calibration at 200 µA
-10%
Bias current monitor ratio
IMONB / IBIAS (nominal 1/100 = 1%)
0.9%
Bias current DMI accuracy
Bias current ≥ 30 mA
Power supply monitor
accuracy
With external mid scale calibration
VCC-RST
VCC reset threshold voltage
VCC voltage level which triggers power-on reset
VCC-RSTHYS
VCC reset threshold voltage
hysteresis
VMONB-FLT
Fault voltage at MONB
(2)
±3
150%
Monitor diode DMI accuracy
(1)
µA
dB
0.9
Sink. BIASPOL = 1
VPD
V
mA
10%
1.0%
1.1%
±10%
–2%
2%
2.5
2.8
100
Fault occurs if voltage at MONB exceeds value
1.1
1.16
V
mV
1.24
V
The bias current can be set below the specified minimum according to the corresponding register setting, however in closed loop
operation settings below the specified value may trigger a fault.
Assured by simulation over process, supply and temperature variation.
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AC ELECTRICAL CHARACTERISTICS
Over recommended operating conditions, with 50Ω output load, open loop operation, VOUT = 2.0Vpp, IBIAS = 80 mA, and RRZTC
= 28.7kΩ unless otherwise noted. Typical operating condition is at VCC =3.3V and TA = 25°C
PARAMETER
CONDITION
MIN
0.01 GHz f < 5 GHz
TYP
MAX
–15
UNIT
SDD11
Differential input return gain
SCD11
Differential to common mode
conversion gain
0.01 GHz < f < 11.1 GHz
tR-OUT
Output rise time
20%–80%, tR-IN < 40 ps, 50Ω load, single-ended,
crosspoint = 50%
28
40
ps
tF-OUT
Output fall time
20%–80%, tF-IN < 40 ps, 50Ω load, single-ended,
crosspoint = 50%
28
40
ps
VO-MIN
Minimum output amplitude
50Ω load, single-ended
VO-MAX
Maximum output amplitude
50Ω load, single-ended
Output Amplitude Stability
50Ω load, single-ended
Modulation voltage step size
50Ω load, 10 Bit Register
VMOD-STEP
DJ
Deterministic output jitter
RJ
5 GHz < f < 11.1 GHz
–20
200 mVpp
Vpp
250
2.5
EQENA = 1 with maximum equalization, K28.5
pattern at 11.3 Gbps, 160mVpp, 600mVpp,
1000mVpp differential input voltage, single-ended
output
5
EQENA = 1, K28.5 pattern at 11.3 Gbps, maximum
equalization with 6” transmission line at the input,
160mVpp, 600mVpp, 1000mVpp input to transmission
line, single-ended output
7
0.2
APC time constant
CAPC 0.01 µF, IPD = 100 µA,
PD coupling ratio CR = 40 (1)
High cross point control range
50Ω load, single-ended
75%
Low cross point contro lrange
50Ω load, single-ended
30%
Cross point stability
50Ω load, single-ended, VIN ≥ 400mVpp
±5%
Transmitter disable time
Rising edge of DIS to IBIAS ≤ 0.1 × IBIAS-NOMINAL (1)
0.05
TON
Disable negate time
Falling edge of DIS to IBIAS ≥ 0.9 × IBIAS-NOMINAL (1)
TINIT1
Power-on to initialize
Power-on to registers ready to be loaded
TINIT2
Initialize to transmit
Register load STOP command to part ready to
transmit valid data (1)
TRESET
DIS pulse width
Time DIS must held high to reset part (1)
(1)
6
Fault assert time
Time from fault condition to FLT high
mV
15
0.6 psRMS
120
(1)
mV
psp-p
TOFF
TFAULT
dB
2.0
Random output jitter
τAPC
dB
–8
1
µs
5
µs
1
ms
10
ms
2
ms
100
ns
50
µs
Assured by simulation over process, supply and temperature variation.
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DETAILED DESCRIPTION
EQUIALIZER
The data signal is applied to an input equalizer by means of the input signal pins DIN+/DIN–, which provide onchip differential 100Ω line-termination. The equalizer is enabled by setting EQENA = 1 (bit 1 of register 0).
Equalization of up to 150mm (6”) of microstrip or stripline transmission line on FR4 printed circuit boards can be
achieved. The amount of equalization is digitally controlled by the two-wire interface and control logic block and
is dependant on the register settings EQADJ[0..7] (register 6). The equalizer can be turned off and bypassed by
setting EQENA = 0 and the supply current is reduced. For details about the equalizer settings, see Table 19.
LIMITER
By limiting the output signal of the equalizer to a fixed value, the limiter removes any overshoot after the input
equalization and provides the input signal for the output driver. Adjustments to the limiter bias current and emitter
follower current can be made to trade off the rise and fall times and supply current. The limiter bias current is
adjusted through LIMCSGN (bit 7 of register 9) and LIMC[0..2] (bits 4, 5 and 6 of register 9). The emitter follower
current is adjusted through EFCSGN (bit 3 of register 9) and EFC[0..2] (bits 0, 1 and 2 of register 9).
HIGH-SPEED OUTPUT DRIVER
The modulation current is sunk from the common emitter node of the limiting output driver differential pair by
means of a modulation current generator, which is digitally controlled by the 2-wire serial interface.
The collector nodes of the output stages are connected to the output pins OUT+ and OUT–. The collectors have
internal 60Ω back termination resistors to VCCO. The outputs are optimized to drive a 50Ω single-ended load
and to obtain the maximum single-ended output voltage of 2.0Vpp, AC coupling and inductive pull-ups to VCC
are required
The polarity of the output pins can be inverted by setting the output polarity switch bit, POL (bit 2 of register 0)
to 1.
MODULATION CURRENT GENERATOR
The modulation current generator provides the current for the current modulator described above. The circuit is
digitally controlled by the 2-wire interface block.
A 10-bit wide control bus, MODC[0..9] (registers 2 and 3), is used to set the desired modulation current, and
therefore, the output voltage. The modulation current can be increased by setting HCENA = 1 (bit 4 of register 1)
and enabling the high modulation current mode, however, the single-ended output voltage should be kept below
2Vpp for the best performance.
The modulation current can be disabled by setting the DIS input pin to a high level or setting ENA = 0 (bit 7 of
register 0). The modulation current is also disabled in a fault condition if the internal fault detection enable
register flag FLTEN is set to 1 (bit 3 of register 0).
DC OFFSET CANCELATION AND CROSS POINT CONTROL
The ONET1141L has DC offset cancellation to compensate for internal offset voltages. The offset cancellation
can be disabled by setting OCDIS = 1 (bit 3 of register 1). To adjust the eye crossing point, set CPENA = 1 (bit 2
of register 8). The crossing point can be moved toward the one level be setting CPSGN = 1 (bit 7 of register 7)
and it can be moved toward the zero level by setting CPSGN = 0. The percentage of shift depends upon the
register settings CPADJ[0..6] (register 7), and the cross point adjustment range bits CPRNG[0..1] (register 8).
Setting CPRNG1 = 0 and CPRNG0 = 0 results in minimum adjustment capability and setting CPRNG1 = 1 and
CPRNG0 = 1 results in maximum adjustment capability.
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BIAS CURRENT GENERATION AND APC LOOP
The bias current generation and APC loop are controlled by means of the 2-wire interface. In open loop
operation, selected by setting OLENA = 1 (bit 4 of register 0) the bias current is set directly by the 10-bit wide
control word BIASC[0..9] (registers 4 and 5). In automatic power control mode, selected by setting OLENA = 0,
the bias current depends on the register settings BIASC[0..9] and the coupling ratio (CR) between the laser bias
current and the photodiode current. CR = IBIAS/IPD. If the photodiode anode is connected to the PD pin (PD pin is
sinking current), set PDPOL = 1 (bit 0 of register 0) and if the photodiode cathode is connected to the PD pin (PD
pin is sourcing current), set PDPOL = 0.
Three photodiode current ranges can be selected by means of the PDRNG[0..1] bits (register 0). The photodiode
range should be chosen to keep the laser bias control DAC, BIASC[0..9], close to the center of its range. This
keeps the laser bias current set point resolution high. For details regarding the bias current setting in open-loop
as well as in closed-loop mode, see Table 19.
The ONET1141L has the ability to source or sink the bias current. The default condition is for the BIAS pin to
source the current (BIASPOL = 0). To act as a sink, set BIASPOL = 1 (bit 2 of register 1).
The bias current is monitored using a current mirror with a gain equal to 1/100. By connecting a resistor between
MONB and GND, the bias current can be monitored as a voltage across the resistor. A low temperature
coefficient precision resistor should be used. The bias current can also be monitored as a 10 bit unsigned digital
word through the 2-wire interface by setting DMONB = 1 (bit 0 of register 10) and removing the resistor to
ground.
ANALOG REFERENCE AND TEMPERATURE SENSOR
The ONET1141L modulator driver is supplied by a single 3.3V±10% supply voltage connected to the VCC and
VCCO pins. This voltage is referred to ground (GND) and can be monitored as a 10 bit unsigned digital word
through the 2-wire interface.
On-chip bandgap voltage circuitry generates a reference voltage, independent of the supply voltage, from which
all other internally required voltages and bias currents are derived.
An external zero temperature coefficient resistor must be connected from the RZTC pin of the device to ground.
This resistor is used to generate a precise, zero-TC current which is required as a reference current for the onchip DACs.
The ONET1141L provides an on-chip temperature sensor which can be monitored as a 10 bit unsigned digital
word through the 2-wire interface.
POWER-ON RESET
The ONE1141L has power on reset circuitry which ensures that all registers are reset to zero during startup.
After the power-on to initialize time (tINIT1), the internal registers are ready to be loaded. The part is ready to
transmit data after the initialize to transmit time (tINIT2), assuming that the chip enable bit ENA is set to 1 and the
disable pin DIS is low. The DIS pin has an internal 10kΩ pull up resistor so the pin must be pulled low to enable
the outputs. The ONET1141L can be disabled using either the ENA control register bit or the disable pin DIS. In
both cases the internal registers are not reset. After the disable pin DIS is set low and/or the enable bit ENA is
set back to 1, the part returns to its prior output settings.
To reduce the disable time, only the output stage can be disabled by setting DISMODE = 1 (bit 1 of register 1).
ANALOG TO DIGITAL CONVERTER
The ONET1141L has an internal 10 bit analog to digital converter (ADC) that converts the analog monitors for
temperature, power supply voltage, bias current and photodiode current into a 10 bit unsigned digital word. The
first 8 most significant bits (MSBs) are available in register 14 and the 2 least significant bits (LSBs) are available
in register 15. Depending on the accuracy required, 8 bits or 10 bits can be read. However, due to the
architecture of the 2-wire interface, in order to read the 2 registers, 2 separate read commands have to be sent.
The ADC is enabled by default so to monitor a particular parameter, select the parameter with ADCSEL[0..1]
(bits 0 and 1 of register 13). Table 1 shows the ADCSEL bits and the parameter that is monitored.
8
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Table 1. ADC Selection Bits and the Monitored
Parameter
ADCSEL1
ADCSEL0
Monitored Parameter
0
0
Temperature
0
1
Supply voltage
1
0
Photodiode current
1
1
Bias current
To digitally monitor the photodiode current, ensure that DMONP = 1 (bit 1 of register 10) and that a resistor is not
connected to the MONP pin. To digitally monitor the bias current, ensure that DMONB = 1 (bit 0 of register 10)
and that a resistor is not connected to the MONB pin. If it is not desired to use the ADC to monitor the various
parameters then the ADC can be disabled by setting ADCDIS = 1 (bit 7 of register 13) and OSCDIS = 1 (bit 6 of
register 13).
The digital word read from the ADC can be converted to its analog equivalent through the following formulas:
Temperature Without a Mid-Point Calibration
Temperature (°C ) = (ADCx - 264 ) / 6
(1)
Temperature With a Mid-Point Calibration
Temperature (°C ) = (T _ cal(°C) + 273) ´ (ADCx + 1362 ) /
(ADC _ cal + 1362 ) – 273
(2)
Power Supply Voltage
Power supply voltage (V ) = 2.25 ´ (ADCx +1380 ) / 1409
(3)
Photodiode Current Monitor
IPD (mA ) = 1.3 ´ ADCx
(4)
Bias Current Monitor
Source mode : IBIAS (mA ) = 0.177 ´ ADCx
Sink mode : IBIAS (mA ) = 0.19 ´ ADCx
(5)
Where:
ADCx = the decimal value read from the ADC
T_cal = the calibration temperature
ADC_cal = the decimal value read from the ADC at the calibration temperature
2-WIRE INTERFACE AND CONTROL LOGIC
The ONET1141L uses a 2-wire serial interface for digital control. The two circuit inputs, SDA and SCK, are
driven, respectively, by the serial data and serial clock from a microprocessor, for example. The SDA and SCK
pins have internal 10kΩ pull ups to VCC. If a common interface is used to control multiple parts, the internal pull
ups can be set to 40kΩ by setting TWITERM to 1 (bit 7 of register 1). This will also set the internal pullup on the
DIS pin to 40 kΩ.
The 2-wire interface allows write access to the internal memory map to modify control registers and read access
to read out the control signals. The ONET1141L is a slave device only which means that it cannot initiate a
transmission itself; it always relies on the availability of the SCK signal for the duration of the transmission. The
master device provides the clock signal as well as the START and STOP commands. The protocol for a data
write transmission is as follows:
1. START command
2. 7 bit slave address (0001000) followed by an eighth bit (value = 0) which is the data write bit (W).
3. 8 bit register address
4. 8 bit register data word
5. STOP command
The first 2 bits of the slave address can be changed to 1 by grounding the ADR0 and ADR1 pins.
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Regarding timing, the ONET1141L is I2C compatible. The typical timing is shown in Figure 2 and complete data
write and read transfers are shown in Figure 3. Parameters for Figure 2 are defined in Table 2.
Bus Idle: Both SDA and SCK lines remain HIGH
Start Data Transfer: A change in the state of the SDA line, from HIGH to LOW, while the SCK line is HIGH,
defines a START condition (S). Each data transfer is initiated with a START condition.
Stop Data Transfer: A change in the state of the SDA line from LOW to HIGH while the SCK line is HIGH
defines a STOP condition (P). Each data transfer is terminated with a STOP condition; however, if the master still
wishes to communicate on the bus, it can generate a repeated START condition and address another slave
without first generating a STOP condition.
Data Transfer: Only one data byte can be transferred between a START and a STOP condition. The receiver
acknowledges the transfer of data.
Acknowledge: Each receiving device, when addressed, is obliged to generate an acknowledge bit. The
transmitter releases the SDA line and a device that acknowledges must pull down the SDA line during the
acknowledge clock pulse in such a way that the SDA line is stable LOW during the HIGH period of the
acknowledge clock pulse. Setup and hold times must be taken into account. When a slave-receiver doesn’t
acknowledge the slave address, the data line must be left HIGH by the slave. The master can then generate a
STOP condition to abort the transfer. If the slave-receiver does acknowledge the slave address but some time
later in the transfer cannot receive any more data bytes, the master must abort the transfer. This is indicated by
the slave generating the not acknowledge on the first byte to follow. The slave leaves the data line HIGH and the
master generates the STOP condition.
SDA
t BUF
tLOW
tR
tHIGH
tF
tHDSTA
SCK
P
S
S
tHDSTA
tHDDAT
tSUDAT
P
tSUSTA
tSUSTO
Figure 2. I2C Timing Diagram
Table 2. Timing Diagram Definitions
SYMBOL
PARAMETER
MIN
MAX
UNIT
400
kHz
fSCK
SCK clock frequency
tBUF
Bus free time between STOP and START conditions
1.3
μs
tHDSTA
Hold time after repeated START condition. After this period, the first clock pulse is generated
0.6
μs
tLOW
Low period of the SCK clock
1.3
μs
tHIGH
High period of the SCK clock
0.6
μs
tSUSTA
Setup time for a repeated START condition
0.6
μs
tHDDAT
Data HOLD time
0
μs
tSUDAT
Data setup time
tR
Rise time of both SDA and SCK signals
300
ns
tF
Fall time of both SDA and SCK signals
300
ns
tSUSTO
Setup time for STOP condition
10
100
0.6
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μs
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Write Sequence
1
7
1
1
8
1
8
1
1
S
Slave Address
Wr
A
Register Address
A
Data Byte
A
P
Read Sequence
1
7
1
1
8
1
1
7
1
1
8
1
1
S
Slave Address
Wr
A
Register Address
A
S
Slave Address
Rd
A
Data Byte
N
P
Legend
S
Start Condition
Wr
Write Bit (bit value = 0)
Rd
Read Bit (bit value = 1)
A
Acknowledge
N
Not Acknowledge
P
Stop Condition
Figure 3. Programming Sequence
REGISTER MAPPING
The register mapping for register addresses 0 (0x00) through 15 (0x0F) are shown in Table 3 through Table 18.
Table 19 describes the circuit functionality based on the register settings.
Table 3. Register 0 (0x00) Mapping – Control Settings
bit 7
ENA
bit 6
PDRNG1
bit 5
PDRNG0
register address 0 (0x00)
bit 4
bit 3
OLENA
FLTEN
bit 2
POL
bit 1
EQENA
bit 0
PDPOL
bit 1
DISMODE
bit 0
LOGENA
bit 1
MODC1
bit 0
MODC0
bit 1
MODC3
bit 0
MODC2
Table 4. Register 1 (0x01) Mapping – Control Settings
bit 7
TWITERM
bit 6
HIEFCENA
bit 5
HIEQGENA
register address 1 (0x01)
bit 4
bit 3
HCENA
OCDIS
bit 2
BIASPOL
Table 5. Register 2 (0x02) Mapping – Modulation Current
bit 7
–
bit 6
–
bit 5
–
register address 2 (0x02)
bit 4
bit 3
–
–
bit 2
–
Table 6. Register 3 (0x03) Mapping – Modulation Current
bit 7
MODC9
bit 6
MODC8
bit 5
MODC7
register address 3 (0x03)
bit 4
bit 3
MODC6
MODC5
bit 2
MODC4
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Table 7. Register 4 (0x04) Mapping – Bias Current
bit 7
–
bit 6
–
bit 5
–
register address 4 (0x04)
bit 4
bit 3
–
–
bit 2
–
bit 1
BIASC1
bit 0
BIASC0
bit 1
BIASC3
bit 0
BIASC2
bit 1
EQADJ1
bit 0
EQADJ0
bit 1
CPADJ1
bit 0
CPADJ0
Table 8. Register 5 (0x05) Mapping – Bias Current
bit 7
BIASC9
bit 6
BIASC8
bit 5
BIASC7
register address 5 (0x05)
bit 4
bit 3
BIASC6
BIASC5
bit 2
BIASC4
Table 9. Register 6 (0x06) Mapping – Equalizer Adjust
bit 7
EQADJ7
bit 6
EQADJ6
bit 5
EQADJ5
register address 6 (0x06)
bit 4
bit 3
EQADJ4
EQADJ3
bit 2
EQADJ2
Table 10. Register 7 (0x07) Mapping – Cross Point Adjust
bit 7
CPSGN
bit 6
CPADJ6
bit 5
CPADJ5
register address 7 (0x07)
bit 4
bit 3
CPADJ4
CPADJ3
bit 2
CPADJ2
Table 11. Register 8 (0x08) Mapping – Cross Point Control Settings
bit 7
IDRV
bit 6
–
bit 5
–
register address 8 (0x08)
bit 4
bit 3
CPREF
–
bit 2
CPENA
bit 1
CPRNG1
bit 0
CPRNG0
Table 12. Register 9 (0x09) Mapping – Limiter Bias Current Adjust
bit 7
LIMCSGN
bit 6
LMC2
bit 5
LIMC1
register address 9 (0x09)
bit 4
bit 3
LIMC0
EFCSGN
bit 2
EFC2
bit 1
EFC1
bit 0
EFC0
bit 1
DMONP
bit 0
DMONB
Table 13. Register 10 (0x0A) Mapping – Monitor Settings
bit 7
–
bit 6
–
bit 5
–
register address 10 (0x0A)
bit 4
bit 3
–
–
bit 2
MONPFLT
Table 14. Register 11 (0x0B) Mapping – Bias Monitor Fault Settings
bit 7
BMF7
bit 6
BMF6
bit 5
BMF5
register address 11 (0x0B)
bit 4
bit 3
BMF4
BMF3
bit 2
BMF2
bit 1
BMF1
bit 0
BMF0
Table 15. Register 12 (0x0C) Mapping – Power Monitor Fault Settings
bit 7
PMF7
bit 6
PMF6
bit 5
PMF5
register address 12 (0x0C)
bit 4
bit 3
PMF4
PMF3
bit 2
PMF2
bit 1
PMF1
bit 0
PMF0
bit 1
ADCSEL1
bit 0
ADCSEL0
Table 16. Register 13 (0x0D) Mapping – ADC Settings
bit 7
ADCDIS
12
bit 6
OSCDIS
bit 5
–
register address 13 (0x0D)
bit 4
bit 3
–
–
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–
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Table 17. Register 14 (0x0E) Mapping – ADC Output (Read Only)
bit 7
ADC9
bit 6
ADC8
bit 5
ADC7
register address 14 (0x0E)
bit 4
bit 3
ADC6
ADC5
bit 2
ADC4
bit 1
ADC3
bit 0
ADC2
Table 18. Register 15 (0x0F) Mapping – ADC Output (Read Only)
bit 7
–
bit 6
–
bit 5
–
register address 15 (0x0F)
bit 4
bit 3
–
–
bit 2
–
bit 1
ADC1
bit 0
ADC0
Table 19. Register Functionality
REGISTER
0
BIT
SYMBOL
FUNCTION
7
ENA
Enable chip bit
1 = Chip enabled. Can be toggled low to reset a fault condition.
0 = Chip disabled
6
5
PDRNG1
PDRNG0
Photodiode current range bits
1X: up to 3080µA / 3µA resolution
01: up to 1540µA / 1.5µA resolution
00: up to 770μA / 0.75μA resolution
4
OLENA
Open loop enable bit
1 = Open loop bias current control,
0 = Closed loop bias current control
3
FLTEN
Fault detection enable bit
1 = Fault detection on
0 = Fault detection off
2
POL
Output polarity switch bit
1: pin 22 = OUT- and pin 21= OUT+
0: pin 22 = OUT+ and pin 21 = OUT-
1
EQENA
Equalizer enable bit
1 = Equalizer is enabled
0 = Equalizer is disabled and bypassed
0
PDPOL
Photodiode polarity bit
1 = Photodiode cathode connected to VCC
0 = Photodiode anode connected to GND
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Table 19. Register Functionality (continued)
REGISTER
1
3
2
5
4
14
BIT
SYMBOL
7
TWITERM
Two wire interface input termination select bit
1 = 40kΩ selected
0 = 10kΩ selected
FUNCTION
6
HIEFCENA
High emitter follower drive current enable bit
1 = High current enabled
0 = High current disabled
5
HIEQGENA
High gain enable for EQ stage (with EQENA = 1)
1 = High gain enabled
0 = High gain disabled
4
HCENA
High modulation current enable bit
1 = High modulation current enabled
0 = High modulation current disabled
3
OCDIS
Offset cancellation disable bit
1 = DC offset cancellation is disabled
0 = DC offset cancellation is enabled
2
BIASPOL
Bias current polarity bit
1 = Bias pin sinks current
0 = Bias pin sources current
1
DISMODE
Disable mode setting bit
1 = Only the output stage is disabled (fast disable mode)
0 = Major parts of the signal path are disabled
0
LOGENA
Low gain enable for input amplifier (with EQENA = 0)
1 = Low gain enabled
0 = Default gain
7
MODC9
Modulation current setting: sets the output voltage
6
MODC8
5
MODC7
4
MODC6
3
MODC5
2
MODC4
1
MODC3
0
MODC2
1
MODC1
0
MODC0
7
BIASC9
Bias curent settings
Closed loop (APC):
6
BIASC8
Coupling ratio CR = IBIAS / IPD, BIASC = 0..1023, IBIAS ≤ 150mA:
5
BIASC7
4
BIASC6
PDRNG = 00 (see above); IBIAS = 0.75µA x CR x BIASC
3
BIASC5
PDRNG = 01 (see above); IBIAS = 1.5µA x CR x BIASC
2
BIASC4
PDRNG = 1X (see above); IBIAS = 3µA x CR x BIASC
1
BIASC3
0
BIASC2
Open loop:
1
BIASC1
IBIAS ~ 150µA x BIASC in source mode
0
BIASC0
IBIAS ~ 100µA x BIASC in sink mode
Output Voltage: 2.3Vpp / 2.5mV steps
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Table 19. Register Functionality (continued)
REGISTER
6
7
8
9
BIT
SYMBOL
7
EQADJ7
FUNCTION
6
EQADJ6
5
EQADJ5
EQENA = 0 (see above)
4
EQADJ4
Equalizer is turned off and bypassed
3
EQADJ3
2
EQADJ2
EQENA = 1 (see above)
1
EQADJ1
Maximum equalization for 00000000
0
EQADJ0
Minimum equalization for 11111111
7
CPSGN
Eye cross-point adjustment setting
6
CPADJ6
CPSGN = 1 (positive shift)
5
CPADJ5
Maximum shift for 1111111
4
CPADJ4
Minimum shift for 0000000
3
CPADJ3
CPSGN = 0 (negative shift)
2
CPADJ2
Maximum shift for 1111111
1
CPADJ1
Minimum shift for 0000000
0
CPADJ0
7
IDRV
6
-
5
-
4
CPREF
3
-
2
CPENA
Cross point adjustment enable bit
1 = Cross point adjustment is enabled
0 = Cross point adjustment is disabled
1
0
CPRNG1
CPRNG0
Cross point adjustment range bits
Minimum adjustment range for 00
Maximum adjustment range for 11
7
LIMCSGN
Limiter bias current sign bit
1 = Decrease limiter bias current
0 = Increase limiter bias current
6
5
4
LIMC2
LIMC1
LIMC0
Limiter bias current selection bits
000 = No change
111 = Maximum current change
3
EFCSGN
Emitter follower sign bit
1 = Decrease emitter follower current
0 = Increase emitter follower current
2
1
0
EFC2
EFC1
EFC0
Emitter follower current selection bits
000 = No change
111 = Maximum current change
Equalizer adjustment setting
Output Driver Tail Current Bit
1 = Output driver tail current is increased
0 = Output driver tail current is set to default
Cross point temperature coefficient selection bit
1 = Reverses the behavior
MM and EQENA = 1: temperature coefficient disabled
MM and EQENA = 0: temperature coefficient enabled
0 = Default condition
MM and EQENA = 1: temperature coefficient enabled
MM and EQENA = 0: temperature coefficient disabled
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Table 19. Register Functionality (continued)
REGISTER
BIT
10
7
-
6
-
5
-
4
-
3
-
2
MONPFLT
Analog photodiode current monitor fault trigger bit
1 = Fault trigger on MONP pin is enabled
0 = Fault trigger on MONP pin is disabled
1
DMONP
Digital photodiode current monitor selection bit (MONP)
1 = Digital photodiode monitor is active (external resistor must not be installed)
0 = Analog photodiode monitor is active (external resistor is required)
0
DMONB
Digital bias current monitor selection bit (MONB)
1 = Digital bias current monitor is active (external resistor must not be installed)
0 = Analog bias current monitor is active (external resistor is required)
7
BMF7
Bias current monitor fault threshold
6
BMF6
With DMONB = 1
5
BMF5
Register sets the value of the bias current that will trigger a fault.
4
BMF4
The external resistor on the MONB pin must be removed to use this feature.
3
BMF3
2
BMF2
1
BMF1
0
BMF0
7
PMF7
Power monitor fault threshold
6
PMF6
With DMONP = 1
5
PMF5
Register sets the value of the photodiode current that will trigger a fault
4
PMF4
The external resistor on the MONP pin must be removed to use this feature.
3
PMF3
2
PMF2
1
PMF1
0
PMF0
7
ADCDIS
ADC disable bit
1 = ADC disabled
0 = ADC enabled
6
OSCDIS
ADC oscillator bit
1 = Oscillator disabled
0 = Oscillator enabled
ADCSEL1
ADCSEL0
ADC input selection bits
00 selects the temperature sensor
01 selects the power supply monitor
10 selects MONP
11 selects MONB
11
12
13
SYMBOL
FUNCTION
5
4
3
2
1
0
16
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Table 19. Register Functionality (continued)
REGISTER
BIT
14
7
ADC9 (MSB)
6
ADC8
5
ADC7
4
ADC6
3
ADC5
2
ADC4
1
ADC3
0
ADC2
7
-
6
-
5
-
4
-
3
-
2
-
1
ADC1
0
ADC0 (LSB)
15
SYMBOL
FUNCTION
Digital representation of the ADC input source (read only)
Digital representation of the ADC input source (read only)
LASER SAFETY FEATURES AND FAULT RECOVERY PROCEDURE
The ONET1141L provides built in laser safety features. The following fault conditions are detected:
1. Voltage at MONB exceeds the voltage at RZTC (1.16V) or, alternately, if DMONB = 1 and the bias current
exceeds the bias current monitor fault threshold set by BMF[0..7] (register 11). When using the digital
monitor, the resistor to ground must be removed.
2. Voltage at MONP exceeds the voltage at RZTC (1.16V) and the analog photodiode current monitor fault
trigger bit, MONPFLT (bit 2 of register 10), is set to 1. Alternately, a fault can be triggered if DMONP = 1 and
the photodiode current exceeds the photodiode current monitor fault threshold set by PMF[0..7] (register 12).
When using the digital monitor, the resistor to ground must be removed.
3. Photodiode current exceeds 150% of its set value,
4. Bias control DAC drops in value by more than 50% in one step.
If one or more fault conditions occur and the fault enable bit FLTEN is set to 1, the ONET1141L responds by:
1. Setting the bias current to zero.
2. Setting the modulation current to zero.
3. Asserting and latching the FLT pin.
Fault recovery is performed by the following procedure:
1. The disable pin DIS and/or the internal enable control bit ENA are toggled for at least the fault latch reset
time.
2. The FLT pin de-asserts while the disable pin DIS is asserted or the enable bit ENA is de-asserted.
3. If the fault condition is no longer present, the part will return to normal operation with its prior output settings
after the disable negate time.
4. If the fault condition is still present, FLT re-asserts once DIS is set to a low level and the part will not return to
normal operation.
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TYPICAL CHARACTERISTICS
Typical operating condition is at VCC = 3.3V, TA = 25°C, IBIASC = 80mA, VOUT = 2VPP, VIN = 400mVpp (unless otherwise noted).
DETERMINISTIC JITTER
vs
MODULATION CURRENT
DETERMINISTIC JITTER
vs
TEMPERATURE
12
8
Deterministic Jitter - pspp
Deterministic Jitter - pspp
10
8
6
4
6
4
2
2
0
300
400
500
600
700
800
900
Modulation Current Register Setting - Decimal
0
-40
1000
-20
0
20
40
60
TA - Free-Air Temperature - °C
Figure 4.
Figure 5.
RANDOM JITTER
vs
MODULATION CURRENT
RANDOM JITTER
vs
TEMPERATURE
1
80
100
0.4
0.9
0.8
Random Jitter - psrms
Random Jitter - psrms
0.3
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.2
0.1
0
300
400
500
600
700
800
900
Modulation Current Register Setting - Decimal
1000
0
-40
-20
Figure 6.
18
0
20
40
60
TA - Free-Air Temperature - °C
80
100
Figure 7.
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TYPICAL CHARACTERISTICS (continued)
Typical operating condition is at VCC = 3.3V, TA = 25°C, IBIASC = 80mA, VOUT = 2VPP, VIN = 400mVpp (unless otherwise noted).
RISE-TIME AND FALL-TIME
vs
MODULATION CURRENT
RISE-TIME AND FALL-TIME
vs
TEMPERATURE
35
35
25
Fall Time
20
15
20
15
10
5
5
400
500
600
700
800
900
Modulation Current Register Setting - Decimal
Fall Time
25
10
0
300
Rise Time
30
Rise Time
Transition Time - ps
Transition Time - ps
30
0
-40
1000
-20
0
20
40
60
TA - Free-Air Temperature - °C
80
Figure 8.
Figure 9.
BIAS CURRENT IN OPEN LOOP MODE
vs
BIAS CURRENT REGISTER SETTING
BIAS CURRENT IN OPEN LOOP MODE
vs
BIAS CURRENT REGISTER SETTING
100
120
180
160
Sink OL Bias Current - mA
Source OL Bias Current - mA
100
140
120
100
80
60
80
60
40
40
20
20
0
0
0
200
400
600
800
1000
Bias Current Register Setting - Decimal
1200
0
200
Figure 10.
400
600
800
1000
Bias Current Register Setting - Decimal
1200
Figure 11.
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TYPICAL CHARACTERISTICS (continued)
Typical operating condition is at VCC = 3.3V, TA = 25°C, IBIASC = 80mA, VOUT = 2VPP, VIN = 400mVpp (unless otherwise noted).
PHOTODIODE MONITOR CURRENT
vs
PHOTODIODE CURRENT
BIAS MONITOR CURRENT
vs
BIAS CURRENT
1.8
0.8
Photodiode Monitor Current - mA
1.6
Bias Monitor Current - mA
1.4
1.2
1
0.8
0.6
0.4
0.6
0.4
0.2
0.2
0
0
20
40
60
80
100
120
Bias Current - mA
140
160
0
180
0
0.2
0.4
0.6
0.8
1
Photodiode Current - mA
Figure 12.
Figure 13.
OUTPUT VOLTAGE
vs
MODC REGISTER SETTING
SUPPLY CURRENT
vs
TEMPERATURE
3
1.2
1.4
1.6
200
190
2.5
Supply Current - mA
SE Output Voltage - V
180
2
1.5
1
170
160
150
140
130
120
0.5
110
0
0
200
400
600
800
1000
Modulation Current Register Setting - Decimal
1200
100
-40
-20
Figure 14.
20
0
20
40
60
TA - Free-Air Temperature - °C
80
100
Figure 15.
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TYPICAL CHARACTERISTICS (continued)
Typical operating condition is at VCC = 3.3V, TA = 25°C, IBIASC = 80mA, VOUT = 2VPP, VIN = 400mVpp (unless otherwise noted).
EYE-DIAGRAM AT 10.31GBPS
VOUT=2VPP, EQ Set to 00
500 mV/div
EYE-DIAGRAM AT 11.3GBPS
VOUT=2VPP, EQ Set to 00, 50% Cross Point
15 ps/div
15 ps/div
500 mV/div
Figure 16.
Figure 17.
EYE-DIAGRAM AT 11.3GBPS
VOUT=2VPP, EQ Set to 00, 30% Cross Point
EYE-DIAGRAM AT 11.3GBPS
VOUT=2VPP, EQ Set to 00, 70% Cross Point
15 ps/div
500 mV/div
500 mV/div
15 ps/div
Figure 18.
Figure 19.
EYE-DIAGRAM AT 11.3GBPS
VOUT=2VPP, EQ Set to 00,
6’’ OF FR4 AT INPUTS
15 ps/div
500 mV/div
Figure 20.
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Copyright © 2012, Texas Instruments Incorporated
Product Folder Link(s) :ONET1141L
21
ONET1141L
SLLSEB7 – MAY 2012
www.ti.com
APPLICATION INFORMATION
Figure 21 and Figure 22 show typical application circuits using the ONET1141L. The modulator must be AC
coupled to the driver for proper operation. The laser driver is controlled via the 2-wire interface SDA/SCK by a
microcontroller. In a typical application, the FLT, MONB and MONP outputs are also connected to the
microcontroller for transceiver management purposes.
The component values in Figure 21 and Figure 22 are typical examples and may be varied according to the
intended application.
DIS
VCC
SDK
0.1μF
PD
ADR0
ADR1
DIS
SCK
SDA
SDA
0.1μF
FLT
VCCO
GND
GND
DIN+
DIN+
MOD-
DIN-
DIN–
MOD+
GND
GND
RZTC
VCCO
FLT
C1
0.1μF
ONET1141L
C2
0.1μF
EA BIAS
0.1μF
EML TOSA
50Ω
Modulator
Anode
0.1μF
0.1μF
BIAS
GND
VCC
COMP
MONP
MONB
50Ω
Laser
PD
RZTC
28.7kΩ
0.1μF
0.01μF
MONB
RMONB
1kΩ
MONP
RMONP
5kΩ
CCOMP
0.01μF
Figure 21. AC Coupled Drive with PD Monitor Cathode Available
22
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Copyright © 2012, Texas Instruments Incorporated
Product Folder Link(s) :ONET1141L
ONET1141L
www.ti.com
SLLSEB7 – MAY 2012
DIS
VCC
SDK
0.1μF
PD
ADR0
ADR1
DIS
SCK
SDA
SDA
0.1μF
FLT
VCCO
GND
GND
DIN+
DIN+
MOD-
DIN-
DIN–
MOD+
GND
GND
RZTC
VCCO
FLT
C1
0.1μF
ONET1141L
C2
0.1μF
EA BIAS
0.1μF
EML TOSA
50Ω
Modulator
Anode
0.1μF
0.1μF
BIAS
GND
VCC
COMP
MONP
MONB
50Ω
Laser
PD
RZTC
28.7kΩ
0.1μF
0.01μF
-3V
MONB
RMONB
1kΩ
MONP
RMONP
5kΩ
CCOMP
0.01μF
Figure 22. AC Coupled Drive with PD Monitor Anode Available
Layout Guidelines
For optimum performance, use 50Ω transmission lines (100Ω differential) for connecting the signal source to the
DIN+ and DIN– pins and 50Ω transmission lines (100Ω differential) for connecting the modulation current
outputs, MOD+ and MOD–, to the laser. The length of the transmission lines should be kept as short as possible
to reduce loss and pattern-dependent jitter.
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Copyright © 2012, Texas Instruments Incorporated
Product Folder Link(s) :ONET1141L
23
PACKAGE OPTION ADDENDUM
www.ti.com
7-Jan-2015
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)
ONET1141LRGER
ACTIVE
VQFN
RGE
24
3000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 100
ONET
1141L
ONET1141LRGET
ACTIVE
VQFN
RGE
24
250
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 100
ONET
1141L
(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)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(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
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.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
7-Jan-2015
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
1-Nov-2019
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
ONET1141LRGER
VQFN
RGE
24
3000
330.0
12.4
4.3
4.3
1.5
8.0
12.0
Q2
ONET1141LRGET
VQFN
RGE
24
250
330.0
12.4
4.3
4.3
1.5
8.0
12.0
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
1-Nov-2019
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
ONET1141LRGER
VQFN
RGE
24
3000
367.0
367.0
38.0
ONET1141LRGET
VQFN
RGE
24
250
367.0
367.0
38.0
Pack Materials-Page 2
GENERIC PACKAGE VIEW
RGE 24
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
Images above are just a representation of the package family, actual package may vary.
Refer to the product data sheet for package details.
4204104/H
PACKAGE OUTLINE
RGE0024B
VQFN - 1 mm max height
SCALE 3.000
PLASTIC QUAD FLATPACK - NO LEAD
4.1
3.9
A
B
0.5
0.3
PIN 1 INDEX AREA
4.1
3.9
0.3
0.2
DETAIL
OPTIONAL TERMINAL
TYPICAL
C
1 MAX
SEATING PLANE
0.05
0.00
0.08 C
2X 2.5
(0.2) TYP
2.45 0.1
7
SEE TERMINAL
DETAIL
12
EXPOSED
THERMAL PAD
13
6
2X
2.5
SYMM
25
18
1
20X 0.5
24
PIN 1 ID
(OPTIONAL)
0.3
0.2
0.1
C A B
0.05
24X
19
SYMM
24X
0.5
0.3
4219013/A 05/2017
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
RGE0024B
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
( 2.45)
SYMM
24
19
24X (0.6)
1
18
24X (0.25)
(R0.05)
TYP
25
SYMM
(3.8)
20X (0.5)
13
6
( 0.2) TYP
VIA
12
7
(0.975) TYP
(3.8)
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:15X
0.07 MIN
ALL AROUND
0.07 MAX
ALL AROUND
SOLDER MASK
OPENING
METAL
EXPOSED
METAL
SOLDER MASK
OPENING
EXPOSED
METAL
NON SOLDER MASK
DEFINED
(PREFERRED)
METAL UNDER
SOLDER MASK
SOLDER MASK
DEFINED
SOLDER MASK DETAILS
4219013/A 05/2017
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
RGE0024B
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
4X ( 1.08)
(0.64) TYP
24
19
24X (0.6)
1
25
18
24X (0.25)
(R0.05) TYP
(0.64)
TYP
SYMM
(3.8)
20X (0.5)
13
6
METAL
TYP
12
7
SYMM
(3.8)
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
EXPOSED PAD 25
78% PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE
SCALE:20X
4219013/A 05/2017
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
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Copyright © 2019, Texas Instruments Incorporated
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