ADN2871 Analog Devices, Inc., ADN2871 Datasheet
ADN2871
Related parts for ADN2871
ADN2871 Summary of contents
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... V, 50 Mbps to 4.25 Gbps, Single-Loop, Laser Diode Driver GENERAL DESCRIPTION The ADN2871 laser diode driver is designed for advanced SFP and SFF modules, using SFF-8472 digital diagnostics. The ADN2871 supports operation from 50 Mbps to 4.25 Gbps. Average power and extinction ratio can be set with a voltage provided by a microcontroller DAC trimmable resistor or digital potentiometer ...
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... ADN2871 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 SFP Timing Specifications............................................................... 5 Absolute Maximum Ratings............................................................ 6 ESD Caution.................................................................................. 6 Pin Configuration and Function Descriptions............................. 7 Optical Waveforms ........................................................................... 8 Multirate Performance Using Low Cost Fabry Perot TOSA NEC NX7315UA .......................................................................... 8 Performance Over Temperature Using DFB Tosa SUMITOMO SLT2486 ...
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... Resistor setpoint mode 25 kΩ Resistor setpoint mode 1.01 kΩ Voltage setpoint mode 1 V Voltage setpoint mode (RPAV fixed at 1 kΩ) 1000 μA Voltage setpoint mode (RPAV fixed at 1 kΩ) 0.9 V Voltage setpoint mode (RERSET fixed at 1 kΩ) mA/V 2.4 V AC-coupled Ω V 0.8 V ADN2871 ...
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... BIAS TEE 80kHz → 27GHz Figure 2. High Speed Electrical Test Single-Ended Output Circuit BIAS TEE 80kHz → 27GHz IMODN R ADN2871 43Ω IMODP BIAS TEE 80kHz → 27GHz Figure 3. High Speed Electrical Test Differential Output Circuit Rev Page ...
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... Time for the falling edge of ALS to when the modulation current rises above 90% of nominal From power-on or negation of FAIL using ALS Time to fault to FAIL on Time Tx_DISABLE must be held high to reset Tx_FAULT. × 3.3V 10μF ADN2871 ...
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... ADN2871 ABSOLUTE MAXIMUM RATINGS Table 3. Parameter V to GND CC IMODN, IMODP All Other Pins Junction Temperature Operating Temperature Range Industrial Storage Temperature Range Junction Temperature (T max) J LFCSP 1 Power Dissipation 2 θ Thermal Impedance JA θ Thermal Impedance JC Lead Temperature (Soldering 10 sec) 1 Power consumption equations are provided in the Power Consumption section ...
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... Supply Ground. 24 IBIAS Laser Diode Bias (Current Sink to Ground GND ALS V DATAN CC IMODP DATAP ADN2871 IMODN GND GND PAVCAP IBIAS CONNECT Figure 6. Pin Configuration—Top View . In dc-coupled mode, CCBIAS can connect Rev Page ADN2871 . CC ...
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... ADN2871 OPTICAL WAVEFORMS V = 3.3 V and T = 25°C, unless otherwise noted. Note: No change to PAVCAP and ERCAP values MULTIRATE PERFORMANCE USING LOW COST FABRY PEROT TOSA NEC NX7315UA (ACQ LIMIT TEST) WAVEFORMS 1000 Figure 7. Optical Eye 2.488 Gbps, 65 ps/DIV, PRBS −4.5 dBm dB, Mask Margin 25% ...
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... Figure 14. Random Jitter vs. Modulation Current, I BIAS 100 20 Figure 15. Deterministic Jitter at 2.488 Gbps vs. Modulation Current BIAS Rev Page ADN2871 MODULATION CURRENT (mA BIAS 100 MODULATION CURRENT (mA BIAS ...
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... ADN2871 DIFFERENTIAL OUTPUT These performance characteristics were measured using the high speed, electrical differential output circuit shown in Figure MODULATION CURRENT (mA) Figure 16. Rise Time vs. Modulation Current MODULATION CURRENT (mA) Figure 17. Fall Time vs. Modulation Current ...
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... TEMPERATURE (°C) ) vs. Temperature with ALS Asserted –50 –30 – TEMPERATURE (°C) Figure 24. IMOD/IMMON Gain vs. Temperature, I TRANSMISSION t ALS _ON Figure 25. ALS Negate Time, 50 μs/DIV ADN2871 90 110 = 20 mA BIAS 90 110 = 30 mA MOD ...
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... ADN2871 FAIL ASSERTED FAULT FORCED ON PAVSET Figure 26. FAIL Assert Time,1 μs/DIV Figure 27. Time to Initialize, Including Reset, 40 ms/DIV Rev Page TRANSMISSION ON POWER SUPPLY TURN ON ...
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... Temperature calibration is required to adjust the modulation current to compensate for variations of the laser characteristics with temperature. CONTROL METHODS The ADN2871 has two methods for setting the average power (P ) and extinction ratio (ER). The average power and AV extinction ratio can be voltage-set using the output of a microcontroller’ ...
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... Figure 29. ADN2871 Using Microconverter Voltage Setpoint Calibration and Monitoring PAVREF MPD PAVSET V GND CC ERREF ERSET GND Figure 30. ADN2871 Using Resistor Setpoint Calibration of Average Power and Extinction Ratio FAIL ALS MPD PAVSET CONTROL PAVREF RPAV 1kΩ GND ERREF ERSET 1kΩ ...
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... PAVSET and ERSET pins, respectively. A resistor is placed between the pin and GND to set the current flowing in each pin, as shown in Figure 30. The ADN2871 ensures that both PAVSET and ERSET are kept 1.23 V above GND. The PAVSET and ERSET resistors are given ...
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... POWER CONSUMPTION The ADN2871 die temperature must be kept below 125°C. The LFCSP has an exposed paddle, which should be connected so that the same potential as the ADN2871 ground pins. Power consumption can be calculated ...
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... LASER DIODE INTERFACING Figure 35 shows the recommended circuit for interfacing the ADN2871 to most TO Can or coax lasers. DFB and FP lasers typically have impedances of 5 Ω Ω and have axial leads. The circuit shown works over the full range of data rates from 155 Mbps to 3.3 Gbps, including multirate operation (with no change to PAVCAP and ERCAP values) ...
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... Alarm if shorted to V designed tied to voltage setting mode only resistor CC setting mode) IBIAS Ignore Table 6. ADN2871 Response to Various Single-Point Faults in AC-Coupled Configuration (as shown in Figure 35) Pin Short CCBIAS Fault state occurs PAVSET Fault state occurs PAVREF Voltage mode: Fault state occurs ...
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... Dimensions shown in millimeters Package Description 24-Lead Lead Frame Chip Scale Package (LFCSP_VQ) 24-Lead Lead Frame Chip Scale Package (LFCSP_VQ) 24-Lead Lead Frame Chip Scale Package (LFCSP_VQ) Rev Page PIN 1 INDICATOR 1 24 2.25 2. 0.23 MIN THE EXPOSED PADDLE MUST BE CONNECTED TO GROUND. Package Option CP-24-1 CP-24-1 CP-24-1 ADN2871 ...
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... ADN2871 NOTES ©2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05228-0-2/07(A) Rev Page ...