ADN2841 Analog Devices, Inc., ADN2841 Datasheet
ADN2841
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ADN2841 Summary of contents
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... Analog Devices. Dual-Loop 50 Mbps–2.7 Gbps GENERAL DESCRIPTION The ADN2841 uses a unique control algorithm to control both the average power and extinction ratio of the laser diode (LD) after initial factory setup. External component count and PCB area are low, since both power and extinction ratio control are fully integrated ...
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... ADN2841–SPECIFICATIONS Parameter LASER BIAS (BIAS) Output Current I BIAS Compliance Voltage I during ALS BIAS ALS Response Time CCBIAS Compliance Voltage MODULATION CURRENT (IMODP, IMODN) Output Current I MOD Compliance Voltage I during ALS MOD Rise Time Fall Time Jitter Pulsewidth Distortion MONITOR PD (MPD, MPD2) ...
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... ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the ADN2841 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality ...
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... Modulation Current Mirror Output Bias Current Mirror Output Supply Ground IDTONE (Requires External Current Sink to Ground) Supply Ground –4– 32-Lead LFCSP 24 IBMON PIN 1 INDICATOR ASET 2 23 IMMON 22 GND3 ADN2841 21 VCC3 PSET 4 TOP VIEW 20 ALS IMPD 5 (Not to Scale) 19 FAIL 18 DEGRADE GND4 7 17 CLKSEL VCC4 8 ) ...
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... Modulation Current Negative Output. Connect to 25 Ω. Supply Ground Modulation Current Positive Output. Connect to laser diode. Modulation Current Positive Output. Connect to laser diode. Supply Ground Supply Ground Laser Diode Bias Current Laser Diode Bias Current Extra Laser Diode Bias when AC-Coupled –5– ADN2841 ...
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... GΩ time constant of 1000 sec, whichever is less. The ADN2841 may be optimized for 2.7 Gbps operation by keeping the LBWSET pin low. This results in a much shorter loop time constant (a 10 reduction). The value of PAVCAP and ERCAP capacitors required for 2 ...
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... Figure 3. Circuitry to Allow Fiber Identification CCBIAS CCBIAS should be connected to the BIAS pin if the laser diode is connected to the ADN2841 using a capacitor. CCBIAS is a current sink to GND. AUTOMATIC LASER SHUTDOWN The ADN2841 ALS allows compliance to ITU-T-G958 (11/94), section 9.7. When ALS is logic high, both bias and modulation currents are turned off ...
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... FU-445SDF-WM1 SHOULD HAVE BYPASS CAPACITORS AS CLOSE AS POSSIBLE TO THE CC ACTUAL SUPPLY PINS ON THE ADN2841 AND THE LASER DIODE USED. Figure 6. 2.7 Gbps Test Circuit, DC-Coupled, Data Not Clocked, Fast Loop Time Constant Selected alarm output levels must TX RX CLK CS × ...
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... SHOULD HAVE BYPASS CAPACITORS AS CLOSE AS POSSIBLE TO THE CC ACTUAL SUPPLY PINS ON THE ADN2841 AND THE LASER DIODE USED. Figure 7. Anyrate Test Circuit, Capacitively Coupled, Data Clocked, Slow Loop Time Constant Selected REV ...
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... NOTES SHOULD HAVE BYPASS CAPACITORS CC AS CLOSE AS POSSIBLE TO THE ACTUAL SUPPLY PINS ON THE ADN2841 AND THE LASER DIODE USED. 10nF 2. THE OP293 HAS BEEN SELECTED BECAUSE 100nH OF ITS GAIN-BANDWIDTH PRODUCT AND SHOULD BE USED IN THIS APPLICATION GND2 ...
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... Frame Chip Scale Package [LFCSP] (CP-32) Dimensions shown in millimeters 5.00 BSC SQ 0.60 MAX 0.50 4.75 BSC TOP BSC SQ VIEW 0.50 0.40 0.30 0.70 MAX 0.65 NOM 0.05 MAX 0.02 NOM 0.30 0.25 REF COPLANARITY 0.23 0.08 0.18 COMPLIANT TO JEDEC STANDARDS MO-220-VHHD-2 –11– ADN2841 0.30 0.23 0.60 MAX PIN 1 0.18 INDICATOR 48 1 5.25 BOTTOM 4.70 VIEW 2. 5.50 REF 0.60 MAX PIN 1 INDICATOR 3.25 BOTTOM SQ 3 ...
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Revision History Location 8/02—Data Sheet changed from REV REV. A. Figure 8 replaced . . . . . . . . . . . . . . . . . . . . . . . . . ...