14 June, 2002
PRINTER
6-11
D
e
tailed
D
escr
iptions
Auto Power Control (APC)
To prevent the intensity of the laser beam from changing because of temperature,
the machine monitors the laser beam with a photodiode (PD). The PD is enclosed
in the laser diode. The PD passes an electrical current to the LD driver IC and this
IC adjusts its output level to keep the laser diode output constant.
The laser diode power level is adjusted on the production line. Do not touch the
variable resistors on the LD unit in the field.
LD Drive Board
LD Driver
LD
PD
VCC
+5VDLF
BAPCSH
BLDDRDAT
BLDON-N
H310D901.WMF