3.3 V Dual-Loop, 50 Mbps to 3.3 Gbps Laser Diode Driver Data Sheet ADN2872 FEATURES GENERAL DESCRIPTION 1 SFP/SFF and SFF-8472 MSA compliant Like the ADN2870, the ADN2872 laser diode driver is designed SFP reference design available for advanced SFP and SFF modules, using SFF-8472 digital Any rate from 50 Mbps to 3.3 Gbps operation diagnostics. The device features dual-loop control of the average Dual-loop control of average power and extinction ratio power and extinction ratio (ER), which automatically compensates Typical rise/fall time: 60 ps for variations in laser characteristics over temperature and aging. Bias current range: 2 mA to 100 mA The laser needs only be calibrated at 25C, eliminating the need Modulation current range: 5 mA to 90 mA for expensive and time consuming temperature calibration. The Laser FAIL alarm and automatic laser shutdown (ALS) ADN2872 supports single-rate operation from 50 Mbps to Bias and modulation current monitoring 3.3 Gbps, or multirate operation from 155 Mbps to 3.3 Gbps. 3.3 V operation With a new alarm scheme, this device avoids the shutdown issue 4 mm 4 mm LFCSP caused by the system transient generated from various lasers. Voltage setpoint control The average power and ER can be set with a voltage provided by Resistor setpoint control a microcontroller digital-to-analog converter (DAC) or by a APPLICATIONS trimmable resistor. The device provides both bias and modulation current monitoring, as well as fail alarms and automatic laser Multirate OC3 to OC48-FEC SFP/SFF modules shutdown. The ADN2872, a SFF-/SFP-compliant laser diode driver, 1/2/4 Fibre Channel SFP/SFF modules can work with the Analog Devices, Inc., ADuC7019, ADuC7020, LX-4 modules and ADuC7023 MicroConverter family and the ADN2890, DWDM/CWDM SFP modules ADN2891, and ADN2892 limiting amplifier family, to form a 1GE SFP/SFF transceiver modules complete SFP/SFF transceiver solution. The ADN2872 is available in a space-saving 4 mm 4 mm LFCSP specified over the 40C to +85C temperature range. Figure 1 shows an application diagram with a microcontroller interface. 1 Protected by U.S. Patent 6,414,974. APPLICATIONS DIAGRAM V CC V V CC CC V CC Tx FAULT L Tx FAIL FAIL ALS IMODN LASER R V CC IMODP MPD DATAP PAVSET ANALOG DEVICES DATAN MICROCONTROLLER 100 I V MOD CC PAVREF DAC R Z IBIAS CONTROL ADC I BIAS RPAV CCBIAS 1k GND ERREF DAC ADN2872 ERSET 1k GND IBMON IMMON PAVCAP ERCAP VCC GND 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 20092016 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 08013-001ADN2872 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Control ......................................................................................... 11 Applications ....................................................................................... 1 Voltage Setpoint Calibration ..................................................... 11 General Description ......................................................................... 1 Resistor Setpoint Calibration .................................................... 13 Applications Diagram ...................................................................... 1 I Monitoring .......................................................................... 13 MPD Revision History ............................................................................... 2 Loop Bandwidth Selection ........................................................ 14 Specifications ..................................................................................... 3 Power Consumption .................................................................. 14 SFP Timing Specifications ........................................................... 4 Automatic Laser Shutdown (Tx Disable) ............................... 14 Absolute Maximum Ratings ............................................................ 5 Bias and Modulation Monitor Currents .................................. 14 ESD Caution .................................................................................. 5 IBIAS Pin ..................................................................................... 14 Pin Configuration and Function Descriptions ............................. 6 Data Inputs .................................................................................. 15 Typical Performance Characteristics ............................................. 7 Laser Diode Interfacing ............................................................. 15 Optical Waveforms ........................................................................... 9 Alarms .......................................................................................... 16 Theory of Operation ...................................................................... 10 Outline Dimensions ....................................................................... 17 Dual-Loop Control..................................................................... 10 Ordering Guide .......................................................................... 17 REVISION HISTORY 9/2016Rev. A to Rev. B Changes to Ordering Guide .......................................................... 17 2/2016Rev. 0 to Rev. A Changes to General Description .................................................... 1 Changes to Figure 5 and Table 4 ..................................................... 6 Updated Outline Dimensions ....................................................... 17 3/2009Revision 0: Initial Version Rev. B Page 2 of 20