ADN2873

3.3 V, 50 Mbps to 4.25 Gbps, Single-Loop, Laser Diode Driver ADN2873 FEATURES SFP/SFF and SFF-8472 MSA compliant SFP reference design available 50 Mbps to 4.25 Gbps operation Automatic average power control Typical 60 ps output rise/fall time VCSEL, DFB, and FP laser support Bias current range: from 2 mA to 100 mA www.DataSheet4U.com Modulation current range: from 5 mA to 90 mA Laser fail alarm and automatic laser shutdown (ALS) Bias and modulation current monitoring Voltage setpoint control Resistor setpoint control 3.3 V supply 24-lead 4 mm × 4 mm LFCSP Pin compatible with ADN2870 GENERAL DESCRIPTION Like the ADN2870, the ADN2873 laser diode driver (LDD) is designed for advanced SFP and SFF modules, using SFF-8472 digital diagnostics. The ADN2873 supports NRZ data transmission operation from 50 Mbps up to 4.25 Gbps. With a new alarm scheme, this device avoids the shutdown issue caused by the system transient generated from various lasers. The ADN2873 monitors the laser bias and modulation currents and it provides fail alarms and ALS. Using setup voltages of a microcontroller DAC or a trimmable resistor voltage divider, the ADN2873 can set up a laser optical average output power and extinction ratio. The optical average power control loop consists of an optical feedback from a photodiode, the comparator, and a status holder. The ADN2873 works easily with the Analog Devices, Inc., ADuC7019/ADuC702x family of MicroConverter® devices and with the ADN289x family of limiting amp...