3.3 V, 50 Mbps to 4.25 Gbps, Single-Loop, Laser Diode Driver Data Sheet ADN2873 FEATURES GENERAL DESCRIPTION SFP/SFF and SFF-8472 MSA compliant Like the ADN2870, the ADN2873 laser diode driver (LDD) is SFP reference design available designed for advanced SFP and SFF modules, using SFF-8472 50 Mbps to 4.25 Gbps operation digital diagnostics. The ADN2873 supports NRZ data transmis- Automatic average power control sion operation from 50 Mbps up to 4.25 Gbps. With a new alarm Typical 60 ps output rise/fall time scheme, this device avoids the shutdown issue caused by the VCSEL, DFB, and FP laser support system transient generated from various lasers. Bias current range: from 2 mA to 100 mA The ADN2873 monitors the laser bias and modulation currents Modulation current range: from 5 mA to 90 mA and it provides fail alarms and ALS. Using setup voltages of a Laser fail alarm and automatic laser shutdown (ALS) microcontroller DAC or a trimmable resistor voltage divider, Bias and modulation current monitoring the ADN2873 can set up a laser optical average output power and Voltage setpoint control extinction ratio. The optical average power control loop consists of Resistor setpoint control an optical feedback from a photodiode, the comparator, and a 3.3 V supply status holder. The ADN2873 works easily with the Analog 24-lead 4 mm 4 mm LFCSP Devices, Inc., ADuC7019/ADuC7020/ADuC7023 family of Pin compatible with ADN2870 MicroConverter devices and with the ADN2890/ADN2891/ APPLICATIONS ADN2892 family of limiting amplifiers to make a complete SFP/SFF transceiver chipset solution. 1/2/4 Fibre Channel SFP/SFF modules Multirate OC3 to OC48-FEC SFP/SFF modules The ADN2873 is pin compatible with the ADN2870 dual-loop LX-4 modules LDD, allowing the same design to work with either device. For DWDM/CWDM laser transmitters dual-loop control applications, refer to the ADN2870 data sheet. HDTV (SMPTE family) laser transmitters The product is available in a space-saving 24-lead, 4 mm 4 mm LFCSP specified over the 40C to +85C temperature range. Figure 1 shows an application diagram of the voltage setpoint control with single-ended laser interface. Figure 36 shows a differential laser interface. APPLICATIONS DIAGRAM V CC V V CC CC V CC L Tx DISABLE Tx FAULT FAIL ALS IMODN LASER R V CC IMODP MPD DATAP ANALOG DEVICES PAVSET DATAN MICROCONTROLLER 100 V CC CONTROL PAVREF R DAC Z IBIAS RPAV ADC 100 1k CCBIAS IMOD GND ERREF DAC ERSET ADN2873 1k GND IBMON IMMON PAVCAP DNC VCC GND GND 1k 470 GND GND Figure 1. Rev. B Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 20082016 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. Technical Support www.analog.com 07493-001ADN2873 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Laser Control .............................................................................. 13 Applications ....................................................................................... 1 Control Methods ........................................................................ 13 General Description ......................................................................... 1 Voltage Setpoint Calibration ..................................................... 13 Applications Diagram ...................................................................... 1 Resistor Setpoint Calibration .................................................... 15 Revision History ............................................................................... 2 I Monitoring .......................................................................... 15 MPD Specifications ..................................................................................... 3 Loop Bandwidth Selection ........................................................ 16 SFP Timing Specifications ........................................................... 5 Power Consumption .................................................................. 16 Absolute Maximum Ratings ............................................................ 6 Automatic Laser Shutdown (Tx Disable) ............................... 16 ESD Caution .................................................................................. 6 Bias and Modulation Monitor Currents .................................. 16 Pin Configuration and Function Descriptions ............................. 7 IBIAS Pin ..................................................................................... 16 Typical Performance Characteristics ............................................. 8 Data Inputs .................................................................................. 17 Single-Ended Output ................................................................... 8 Laser Diode Interfacing ............................................................. 17 Differential Output ....................................................................... 9 Alarms .......................................................................................... 18 Performance Characteristics ..................................................... 10 Outline Dimensions ....................................................................... 19 Optical Waveforms ......................................................................... 12 Ordering Guide .......................................................................... 19 Theory of Operation ...................................................................... 13 REVISION HISTORY 8/2016Rev. A to Rev. B Changes to Ordering Guide .......................................................... 19 1/2016Rev. 0 to Rev. A Changed NC to DNC .................................................... Throughout Changes to General Description Section ...................................... 1 Change to Figure 6 and Table 4 ...................................................... 7 Updated Outline Dimensions ....................................................... 19 Changes to Ordering Guide .......................................................... 19 6/2008Revision 0: Initial Version Rev. B Page 2 of 20