xmt5370622 ETC-unknow, xmt5370622 Datasheet - Page 3

• Manufacturer Part Number: xmt5370622
• Description: Mb/s Logic Interface Laser Transmitter
• Manufacturer: ETC-unknow

XMT5370622 Block Diagram
Functional Description
The ECL inputs allow operation
from many logic families and both
single-ended or differential signals.
As both DATA and DATA are
internally tied to V
ended operation the unused input
requires no connection or biasing.
The disable function disables the
laser bias and modulator. The
switching threshold is V
If this input is not connected the
module is enabled. This input may
be connected to a CMOS HI or
tied to V
DATA
DATA
DISABLE
CC
to disable.
INPUT
ECL
BB
, for single
CC
-3.2 V.
The module provides the
necessary bias and modulation
control to maintain the extinction
ratio at better than 8.2 dB and the
waveform is compliant with
SONET/SDH Eyemask standard
G.957.
The laser bias control loop
compensates for temperature
induced variations in laser
performance. The bias current
monitor indicates the amount of
dc current supplied to the laser.
(This is approximately the laser
threshold current).
MODULATOR
LASER
LASER BIAS
LASER BIAS
CONTROL
DRIVER
LASER
(rear facet monitor)
PHOTODIODE
3
The rear facet monitor is a signal
proportional to the laser output
power. This can be used as part of
a HI/LO light alarm.
In the absence of data the laser
will emit a mean optical power
within the specified limits. The
extinction ratio and duty cycle
distortion are specified assuring a
50% duty cycle at the correct data
rate.
LASER BIAS
MONITOR
REAR FACET
MONITOR