DIAGNOSTICS
Test Points and LEDs
10DEC05
DG4825-1
Page
178 of 180
Table 24
Test Points on the LASER DRIVER BOARD A17
Name
Description
Expected Signal
AGND
Circuit ground
0.0 V DC
VN5
------
–5.00 - –5.50 V DC
LPN
Power to the LASER
•
LASER de-energized - 0.0 V DC
•
Threshold - 0.0 V DC
•
LASER energized - –5.0 V DC
LEN
-----
•
LASER de-energized - 0.0 V DC
•
Threshold - –5.0 V DC
•
LASER energized - –5.0 V DC
Iop
----
•
LASER de-energized - –5.0 V DC
•
Threshold - –4.25 to –4.75 V DC
•
LASER energized - –3.35 to –4.35 V DC
Vpd
-----
•
LASER de-energized - –2.3 to –2.5 V DC
•
Threshold - –2.6 V DC
•
LASER energized - –2.9 V DC
Buf_BF
-----
•
LASER de-energized - 0.0 V DC
•
Threshold - –0.06 to –0.08 V DC
•
LASER energized - –1.0 to –1.2 V DC