ADN2847 Analog Devices, Inc., ADN2847 Datasheet
ADN2847
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ADN2847 Summary of contents
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... Gigabit Ethernet DWDM dual MPD wavelength control GENERAL DESCRIPTION The ADN2847 uses a unique control algorithm to control both average power and extinction ratio of the laser diode (LD) after initial factory setup. External component count and PCB area are low, as both power and extinction ratio control are fully integrated ...
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... ADN2847 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Diagrams.......................................................................... 4 Absolute Maximum Ratings............................................................ 5 Thermal Resistance ...................................................................... 5 ESD Caution.................................................................................. 5 Die Pad Coordinates ........................................................................ 6 Pin Configurations and Function Descriptions ........................... 7 Theory of Operation ........................................................................ 9 Control........................................................................................... 9 Loop Bandwidth Selection .......................................................... 9 REVISION HISTORY 10/06—Rev Rev. A Updated Format ...
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... V % Low Loop Bandwidth selection sec LBWSET = GND sec LBWSET = Data and clock inputs are ac-coupled Ω ps See Figure 2 ps See Figure Internal 30 kΩ Pull- User to supply current sink in the range of 50 μ MHz ADN2847 ...
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... The high speed performance for the die version of ADN2847 can be achieved when using the bonding diagram shown in Figure 6. 2 Measured into a 25 Ω load using a 11110000 pattern at 2.5 Gbps. 3 When the voltage on DATAP is greater than the voltage on DATAN, the modulation current flows in the IMODP pin. ...
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... Rating 4.2 V Table 3. Thermal Resistance −0 0 Package Type 48-lead LFCSP −40°C to +85°C 32-lead LFCSP −65°C to +150°C 150°C (T max − θ ESD CAUTION 300°C Rev Page ADN2847 θ Unit JA 25 °C/W 32 °C/W ...
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... ADN2847 DIE PAD COORDINATES 2620µm GND2 GND2 IMMON V 3 FAIL CC IDTONE IBMON GND3 ALS GND2 IMODN IMODN GND2 IMODP IMODP GND2 GND2 I BIAS I BIAS CCBIAS GND ASET PSET IMPD IMPDMON2 LBWSET ERSET GND IMPDMON Figure 5. Metallization Photograph 1 Table 4. Die Pad Coordinates ...
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... Fail Alarm Output. Automatic Laser Shutdown. Supply Voltage. Rev Page ADN2847 LBWSET 1 24 IBMON ASET 2 PIN 1 23 IMMON INDICATOR ERSET 3 22 GND3 PSET 4 ADN2847 CC IMPD 5 20 ALS TOP VIEW 19 FAIL IMPDMON 6 18 DEGRADE GND4 CLKSEL CC Figure 8. 32-Lead LFCSP . CC ...
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... ADN2847 Pin Number 48-Lead 32-Lead Mnemonic 31 22 GND3 32 23 IMMON 33 24 IBMON 34 N/A GND2 35 N/A IDTONE 36 N/A GND2 37 N/A GND2 IMODN 40 N/A IMODN 41 27 GND2 42 28 IMODP 43 N/A IMODP 44 29 GND2 45 30 GND2 BIAS 47 N/A I BIAS 48 32 CCBIAS Description Supply Ground. Modulation Current Mirror Output. ...
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... Figure 9. Laser Transfer Function CONTROL A monitor photodiode (MPD) is required to control the LD. The MPD current is fed into the ADN2847 to control the power and extinction ratio, continuously adjusting the bias current and modulation current in response to the changing threshold current and light-to-current slope efficiency of the laser. ...
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... IDTONE pin and ground. There is a gain of two from this pin to the I Figure 12 shows how the AD9850/AD9851 or the AD9834 can be used with the ADN2847 to allow fiber identification. If the ID_TONE function is not used, the IDTONE pin should be tied to V ...
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... CC POWER CONSUMPTION The ADN2847 die temperature must be kept below 125°C. Both LFCSP packages have an exposed paddle that should be connected in such a manner that is at the same potential as the ADN2847 ground pins. The θ for both packages is specified in the JA Absolute Maximum Ratings section. Power consumption can be ...
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... CC GND 22nF PAVCAP 22nF ERCAP SHOULD HAVE BYPASS CAPACITORS CLOSE AS POSSIBLE TO THE ACTUAL SUPPLY PINS ON THE ADN2847 AND THE LASER DIODE USED. CONSERVATIVE DECOUPLING WOULD INCLUDE 100pF CAPACITORS IN PARALLEL WITH 10nF CAPACITORS 100nF 100nF 100nF 10µF GND ...
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... CC GND 1µF PAVCAP 1µF ERCAP SHOULD HAVE BYPASS CAPACITORS CLOSE AS POSSIBLE TO THE ACTUAL SUPPLY PINS ON THE ADN2847 AND THE LASER DIODE USED. CONSERVATIVE DECOUPLING WOULD INCLUDE 100pF CAPACITORS IN PARALLEL WITH 10nF CAPACITORS 100nF 100nF 10µF GND ADN2847 ...
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... ADN2847 OUTLINE DIMENSIONS PIN 1 INDICATOR 12° MAX 1.00 0.85 0.80 SEATING PLANE PIN 1 INDICATOR 1.00 12° MAX 0.85 0.80 SEATING PLANE 5.00 BSC SQ 0.60 MAX 0.50 BSC TOP 4.75 VIEW BSC SQ 0.50 0.40 0.30 0.80 MAX 0.65 TYP 0.05 MAX 0.02 NOM 0.30 COPLANARITY 0.20 REF 0.23 0.08 0.18 COMPLIANT TO JEDEC STANDARDS MO-220-VHHD-2 Figure 18. 32-Lead Lead Frame Chip Scale Package [LFCSP_VQ × Body, Very Thin Quad ...
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... ADN2847ACPZ-32-RL7 −40°C to +85°C ADN2847ACP-48 −40°C to +85°C ADN2847ACP-48-RL −40°C to +85°C 1 ADN2847ACPZ-48 −40°C to +85°C EVAL-ADN2847-32-OP EB-ADN2847/8-32- Pb-free part. Package Description 32-Lead Lead Frame Chip Scale Package [LFCSP_VQ] 32-Lead Lead Frame Chip Scale Package [LFCSP_VQ] ...
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... ADN2847 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C02745-0-10/06(A) Rev Page ...