Dual-Loop 50 Mbps–2.7 Gbps
Laser Diode Driver
a
ADN2841
FEATURES
GENERAL DESCRIPTION
50 Mbps to 2.7 Gbps Operation
Typical Rise/Fall Time 80 ps
The ADN2841 uses a unique control algorithm to control both
average power and extinction ratio of the laser diode (LD) after
initial factory set up. External component count and PCB area are
low as both power and extinction ratio control are fully integrated.
Programmable alarms are provided for laser fail (end of life) and
laser degrade (impending fail).
Bias Current Range 2 to 100 mA
Modulation Current Range 5 to 80 mA
Monitor Photodiode Current 50 ꢀA to 1200 ꢀA
Closed-Loop Control of Power and Extinction Ratio
Laser Fail and Laser Degrade Alarms
Automatic Laser Shutdown, ALS
Dual MPD Functionality for DWDM
Optional Clocked Data
The ADN2841 has circuitry for a second monitor photodiode
which enables DWDM wavelength control.
Full Current Parameter Monitoring
5 V Operation
48-Lead LFCSP Package
32-Lead LFCSP Package (Reduced Functionality)
APPLICATIONS
DWDM Dual MPD Wavelength Fixing
SONET OC-1/3/12/48
SDH STM-1/4/16
Fiber Channel
Gigabit Ethernet
FUNCTIONAL BLOCK DIAGRAM
V
CC
V
CC
IMODN
LD
V
CC
IMODP
MPD
IMPD
DATAP
DATAN
CLKP
CLKN
I
MOD
IMPD2
PSET
CONTROL
GND
IBIAS
ASET
I
BIAS
GND
GND
ERSET
ADN2841
GND
ERCAP
PAVCAP
GND
IDTONE
LBWSET
GND
REV. 0
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use, norforanyinfringementsofpatentsorotherrightsofthirdpartiesthat
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
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Tel: 781/329-4700
Fax: 781/326-8703
www.analog.com
© Analog Devices, Inc., 2001