Pioneer CX-692 Manuel d'entretien - Page 2

Parcourez en ligne ou téléchargez le pdf Manuel d'entretien pour {nom_de_la_catégorie} Pioneer CX-692. Pioneer CX-692 29 pages. Dvd/cd mechanism unit

Imprimer la page
CX-692

1. Circuit Description

1.1 APC circuit
-
APC (Automatic Power Control) circuit
[Fig. 1 CD and Fig. 2 DVD]
Since the optical output of laser beam diodes carries a
large negatived temperature characteristic, necessary
optical power cannot be acquired when driven at a
lower current level.
The APC circuit is a circuit to
control the current levels so that the output of the
monitor diode may become constant.
the voltage occurring between the LD and the drive
Q104
PICKUP UNIT
8
VPS
OUT
1
2
By measuring
IC103 TA1254AF
45 LDO1
MDI1
44
IC101
7
VCC
CP
2
4
transistor, the LD current can be found out and such
current value should be within ±20% of the value
indicated on the pickup unit flexible P.C. board when
handling the CD and should be 50mA or less when
handling the DVD.
IM
3
PICKUP UNIT
Fig. 2
GND
Fig. 1