ADN2525 Analog Devices, Inc., ADN2525 Datasheet
ADN2525
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ADN2525 Summary of contents
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... Gbps Active Back-Termination, Differential Laser Diode Driver GENERAL DESCRIPTION The ADN2525 laser diode driver is designed for direct modula- tion of packaged laser diodes having a differential resistance ranging from 5 Ω Ω. The active back-termination technique provides excellent matching with the output transmission lines while reducing the power dissipation in the output stage ...
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... ADN2525 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Thermal Specifications ................................................................ 4 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. 6 Typical Performance Characteristics ............................................. 7 Theory of Operation ........................................................................ 9 Input Stage..................................................................................... 9 REVISION HISTORY 8/06—Rev Rev. A Changes to Format .............................................................Universal Changes to Features and Figure 1................................................... 1 Changes to Table 1 ...
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... 157 176 mA Rev Page ADN2525 Test Conditions/Comments ALS = high IBIAS = 100 mA IBIAS = Ω Ω differential LOAD ALS = high Includes pulse-width distortion PWD = ABS(T − T )/2 HIGH LOW 5 GHz < f < 10 GHz Ω differential 0 f < ...
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... The pattern used is K28.5 (00111110101100000101 10.7 Gbps rate. 5 Only includes current in the ADN2525 VCC pins. 6 Includes current in ADN2525 VCC pins and dc current in IMODP and IMODN pull-up inductors. See the Power Consumption section for total supply current calculation. THERMAL SPECIFICATIONS Table 2. Parameter Min θ ...
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... VCC − 0.4 V other conditions above those indicated in the operational VCC + 0.3 V section of this specification is not implied. Exposure to absolute 150 °C maximum rating conditions for extended periods may affect +150 °C device reliability. 300 °C Rev Page ADN2525 ...
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... VCC 14 DATAP 15 DATAN 16 VCC Exposed Pad Pad MSET BSET 12 1 PIN 1 INDICATOR NC IBMON 2 11 ADN2525 ALS IBIAS 3 10 TOP VIEW GND GND 4 9 (Not to Scale CONNECT Figure 4. Pin Configuration I/O Description Input Modulation Current Control Input N/A No Connect—Leave Floating Input Automatic Laser Shutdown ...
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... Rev Page ADN2525 DIFFERENTIAL MODULATION CURRENT (mA) Figure 8. Deterministic Jitter vs. IMOD IBIAS = 100mA IBIAS = 50mA IBIAS = 10mA DIFFERENTIAL MODULATION CURRENT (mA) Figure 9. Total Supply Current vs. IMOD 1 ...
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... ADN2525 0 –5 –10 –15 –20 –25 –30 –35 – FREQUENCY (GHz) Figure 11. Differential |S22 RISE TIME (ps) Figure 12. Worst-Case Rise Time Distribution (VCC = 3.07 V, IBIAS = 100 mA, IMOD = 80 mA ...
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... THEORY OF OPERATION As shown in Figure 1, the ADN2525 consists of an input stage and two voltage-controlled current sources for bias and modulation. The bias current is available at the IBIAS pin controlled by the voltage at the BSET pin and can be monitored at the IBMON pin. The differential modulation current is available at the IMODP and IMODN pins ...
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... Rev Page IBIAS and IMOD Disabled Enabled Enabled VCC VCC 100Ω ALS 50kΩ 2kΩ Figure 24. Equivalent Circuit of the ALS Pin VCC 50Ω FROM INPUT STAGE 800Ω 200Ω ADN2525 GND Figure 25. Generation of Modulation Current on the ADN2525 IMODP IMOD IMODN ...
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... MSET pin able to drive 80 mA modulation currents through the differential load, the output stage of the ADN2525 (the IMODP and IMODN pins) must be ac-coupled to the load. The voltages at these pins have a dc component equal to VCC and an ac component with single-ended, peak-to-peak amplitude of IMOD × ...
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... In practice, many TOSAs have differential resistance less than 50 Ω. In this case, with 50 Ω differential transmission lines connecting the ADN2525 to the load, the load end of the transmission lines are misterminated. This mistermination leads to signal reflections back to the driver. The excellent back-termination in the ADN2525 absorbs these reflections, preventing their reflection back to the load ...
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... The data signal source must be connected to the DATAP and DATAN pins of the ADN2525 using 50 Ω transmission lines. The modulation current outputs, IMODP and IMODN, must be connected to the load (TOSA) using 50 Ω ...
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... To calculate the headroom at the modulation current pins (IMODP and IMODN), the voltage has a dc component equal to VCC due to the ac-coupled configuration and a swing equal to IMOD × 25 Ω. For proper operation of the ADN2525, the voltage at each modulation output pin should be within the normal operation region shown in Figure 30. ...
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... Body, Very Thin Quad (CP-16-3) Dimensions shown in millimeters Package Description 16-Lead LFCSP_VQ, 50-Piece Waffle Pack 16-Lead LFCSP_VQ, 250-Piece Reel 16-Lead LFCSP_VQ, 7” 1,500-Piece Reel Rev Page 0.50 0.40 0. 1.50 SQ 1.35 EXPOSED PAD 4 5 0.25 MIN Package Option CP-16-3 CP-16-3 CP-16-3 ADN2525 Branding F06 F06 F06 ...
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... ADN2525 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05077-0-8/06(A) T Rev Page ...