10.7 Gbps Active Back-Termination, Differential Laser Diode Driver Data Sheet ADN2525 FEATURES GENERAL DESCRIPTION Up to 10.7 Gbps operation The ADN2525 laser diode driver is designed for direct modula- Very low power: 670 mW (IBIAS = 40 mA, IMOD = 40 mA) tion of packaged laser diodes having a differential resistance Typical 24 ps rise/fall times ranging from 5 to 50 . The active back-termination technique Full back-termination of output transmission lines provides excellent matching with the output transmission lines Compatible with XMD-MSA TOSA while reducing the power dissipation in the output stage. The Drives TOSAs with resistances ranging from 5 to 50 back-termination in the ADN2525 absorbs signal reflections PECL-/CML-compatible data inputs from the TOSA end of the output transmission lines, enabling Bias current range: 10 mA to 100 mA excellent optical eye quality to be achieved even when the Differential modulation current range: 10 mA to 80 mA TOSA end of the output transmission lines is significantly Automatic laser shutdown (ALS) misterminated. The small package provides the optimum 3.3 V operation solution for compact modules where laser diodes are packaged Compact 3 mm 3 mm LFCSP in low pin-count optical subassemblies. Voltage input control for bias and modulation currents The modulation and bias currents are programmable via the XFP-compliant bias current monitor MSET and BSET control pins. By driving these pins with Optical evaluation board available control voltages, the user has the flexibility to implement various average power and extinction ratio control schemes, APPLICATIONS including closed-loop control and look-up tables. The automatic SONET OC-192 optical transceivers laser shutdown (ALS) feature allows the user to turn on/off the SDH STM-64 optical transceivers bias and modulation currents by driving the ALS pin with the 10 Gb Ethernet optical transceivers proper logic levels. XFP/X2/XENPAK/XPAK/MSA 300 optical modules SR and VSR optical links The product is available in a space-saving 3 mm 3 mm LFCSP specified from 40C to +85C. FUNCTIONAL BLOCK DIAGRAM VCC ALS VCC ADN2525 VCC IMODP 50 50 50 IMOD IMODN GND VCC DATAP DATAN IBMON IBIAS 800 800 200 200 200 2 MSET GND BSET 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 20052017 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Technical Support www.analog.com Trademarks and registered trademarks are the property of their respective owners. 05077-001ADN2525 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Bias Current ...................................................................................9 Applications ....................................................................................... 1 Automatic Laser Shutdown (ALS) ........................................... 10 General Description ......................................................................... 1 Modulation Current ................................................................... 10 Functional Block Diagram .............................................................. 1 Load Mistermination ................................................................. 12 Revision History ............................................................................... 2 Power Consumption .................................................................. 12 Specifications ..................................................................................... 3 Applications Information .............................................................. 13 Thermal Specifications ................................................................ 4 Typical Application Circuit ....................................................... 13 Absolute Maximum Ratings ............................................................ 5 Layout Guidelines....................................................................... 13 ESD Caution .................................................................................. 5 Design Example .......................................................................... 14 Pin Configuration and Function Descriptions ............................. 6 Outline Dimensions ....................................................................... 15 Typical Performance Characteristics ............................................. 7 Ordering Guide .......................................................................... 15 Theory of Operation ........................................................................ 9 Input Stage ..................................................................................... 9 REVISION HISTORY 4/2017Rev. A to Rev. B Changed CP-16-3 to CP-16-22 .................................... Throughout Updated Outline Dimensions ....................................................... 15 Changes to Ordering Guide .......................................................... 15 8/2006Rev. 0 to Rev. A Changes to Format ............................................................. Universal Changes to Features and Figure 1 ................................................... 1 Changes to Table 1 ............................................................................ 3 Changes to Table 3 ............................................................................ 5 Changes to Figure 19 ........................................................................ 9 Changes to Figure 25 ...................................................................... 10 Changes to Modulation Current Section and Figure 29 ........... 11 Changes to Typical Application Circuit Section......................... 13 Changes to Ordering Guide .......................................................... 15 3/2005Revision 0: Initial Version Rev. B Page 2 of 16