Datasheet

MAX3996
3.0V to 5.5V, 2.5Gbps VCSEL
and Laser Driver
6 _______________________________________________________________________________________
Pin Description
PIN NAME FUNCTION
1TC
Temperature Compensation Set. The resistor at TC programs the temperature-increasing component
of the laser-modulation current.
2 FAULT Fault Indicator. See Table 1.
3, 9 GND Ground
4
TX_DISABLE
Transmit Disable. Laser output is disabled when TX_DISABLE is high or left unconnected. The laser
output is enabled when this pin is asserted low.
5 PORDLY
Power-On Reset Delay. A capacitor connected between PORDLY and GND can be used to extend the
delay for the power-on reset circuit. See the Design Procedure section.
6, 16, 19
V
CC
Supply Voltage
7 IN+ Noninverting Data Input
8 IN- Inverting Data Input
10 MON1
Attaches to the emitter of the bias driving transistor through a 10Ω resistor. See the Design Procedure
section.
11 MON2 This pin attaches to the emitter of the bias driving transistor. See the Design Procedure section.
12 COMP
A capacitor connected from this pin to ground sets the dominant pole of the APC loop. See the Design
Procedure section.
13 MD Monitor Diode Connection. MD is used for automatic power control.
14 SHDNDRV Shutdown Driver Output. Provides a redundant laser shutdown.
15 BIAS Laser Bias Current Output
17 OUT+ Positive Modulation-Current Output. Current flows from this pin when input data is high.
18 OUT- Negative Modulation-Current Output. Current flows to this pin when input data is high.
20 MODSET A resistor connected from this pin to ground sets the desired modulation current.
EP
Exposed Pad
Ground. This must be soldered to the circuit board ground for proper thermal and electrical
performance. See the Layout Considerations section.