ADN2843 Analog Devices, ADN2843 Datasheet
ADN2843
Related parts for ADN2843
ADN2843 Summary of contents
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... No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. 10.709 Gb/s LASER DIODE DRIVER Chipset GENERAL DESCRIPTION The ADN2843 chipset uses a unique control algorithm to control both average power and extinction ratio of the laser diode, LD, after initial factory set-up. The chipset consists of two components ...
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... PRELIMINARY TECHNICAL DATA ADN2843 ( Vcc=3.3V 10%, All specifications Tmin to Tmax unless otherwise noted. Typical values specified at 25 Parameter LASER BIAS (IBIAS) Output current Ibias Ibias during ALS ALS shutdown response time Compliance voltage MODULATION CURRENT (IMODP) Output Current Imod Compliance Voltage Imod during ALS ...
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... Industrial …………………….- +85 C Storage Temperature Range..- +150 C Junction Temperature Range (Tj max) ….+125 C Model Temperature Range ADN2843XXX(1) Chipset -40’C to +85’C ADN2843XXX(2) Chipset -40’C to +85’C Exposed Paddle should be soldered to the most negative supply of the ADN2844 ...
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... Figure 2: Laser Transfer Function CONTROL A monitor photo diode, MPD, is required to control the LD. The MPD current is fed into the ADN2843 to control the power and extinction ratio, continuously adjusting the bias current and modulation current in response to the laser’s changing threshold current and light to current, LI, slope (slope efficiency) ...
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... GND. The capacitors should be low leakage multi-layer ceramic capacitors with an insulation resistance >100G >1000s, whichever is the lower. ALARMS The ADN2843 alarms are designed to allow interface compliance to ITU-T-G958 (11/94) section 10.3..1.1.2 (transmitter fail) and section 10.3.1.1.3 (transmitter degrade). The ADN2843 has two alarms, DEGRADE and FAIL ...
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... VCC to properly disable it. Note that using ID tones during transmission may cause optical eye degradation. AUTOMATIC LASER SHUTDOWN The ADN2843 ALS allows compliance to ITU-T-G958 (11/94), section 9.7. When ALS is asserted, both bias and modulation currents are turned off. Correct operation of ALS can be confirmed by the fail alarm being raised when ALS is asserted ...
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... Modulation current control input (Control circuit sinks IMOD/10 from pin to GND) Bias current control input (Control circuit sinks IBIAS/10 from pin to GND) Negative Supply Positive supply. Bias current Modulation current Negative Supply VCC connection for IMODN termination resistor Negative Supply Positive supply Positive supply Positive supply - 7 - ADN2843 ...
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... PRELIMINARY TECHNICAL DATA ADN2843 PACKAGE OUTLINE Both the ADN2844 and the ADN2845 are available as bare die. The ADN2844 is also available in 5mm x 5mm 32 pin LFCSP. GND3 VCC3 IBIAS_CTRL GND2 IMOD_CTRL CCBIAS GND (NC5) LBWSET ADN2844 Bond Pad Size: 115u sq Bond Pad Pitch: >200u Die Size: 3mm x 2 ...
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... GND VCC VCC ASET IDTONE ERSET IMMON PSET ADN2844 GND IMPD IMPDMON DEGRADE IMPDMON2 IMPD2 10nF VCC 22nF 22nF ADN2843 application circuit VCC VCC 10nF MPD VCC 10nF VCC 24 IBMON ‡ ‡ ALS 1K 1K FAIL 10K GND GND 17 ADN2843 ...