SY88922_11 Datasheet, PDF (1/6 Pages) Micrel Semiconductor – SDH/SONET 2.5Gbps LASER DIODE DRIVER

Micrel, Inc.
SDH/SONET 2.5Gbps
LASER DIODE DRIVER
SY88922
SY88922
FEATURES
DESCRIPTION
■ Up to 2.5Gbps operation
■ 25mA peak drive current
■ Separate modulation control
■ Separate output enable for laser safety
■ Differential inputs for data
■ 75KΩ input pulldown resistor
■ Designed for use with SY88923, SY88904 or SY88905
■ Available in a tiny 10-pin (3mm) MSOP
The SY88922 is a high-speed current switch for driving
a semiconductor laser diode in optical transmission
applications. The output current, or modulation current
IMOD, is DC current controlled by IRSET, current through
the resistor RSET. The output OUT is HIGH when output
enable is HIGH.
The device incorporates complementary open collector
outputs with a capability of driving peak current of 25mA.
The resistor REXT must be placed between /OUT and
VCC to dissipate the worst case power. RSER is
recommended to compensate for laser diode matching
issues.
The SY88922 utilizes the high performance bipolar
ASSET™ technology.
APPLICATIONS
■ 1.25Gbps Gigabit Ethernet
■ 531Mbps and 1062Mbps Fibre Channel
■ 622Mbps SONET
■ Gigabit Interface Converter
■ 2.5Gb/s SDH/SONET
BLOCK DIAGRAM
VCC
REXT
OUT
DIN
Internal Logic
DIN
IMOD
EN
BIAS
Control
40X
VREF
Modulation Control
GND
RSET
M9999-091906
[e-mail] or [phone]
RSET
1
OUT
RSER
to Laser Diode
VCC
GND
Rev.: D Amendment: /0
Issue Date: September 2006