Service manual

45
VSX-918V-K
5
6 7 8
5
6 7 8
A
B
C
D
E
F
5.2 DETECTION CIRCUIT
MAIN ASSY
IC9001
(U-P)
Pin72
DC PROT
Normal : +5 V
DC Detect : 0 V
FL
POWER AMP
POWER AMP
XPROTECT
(refer 4)
1. DC Derection Circuit Diagram : Example of VSX-918V/KUXJ/CA
2. Overload Detection Circuit Diagram: Example of VSX-918V/KUXJ/CA FRONT Channel
3. Fan Stop Protection Circuit Diagram
POWER PACK ASSY
POWER PACK ASSY
MAIN ASSY
IC603(2/3)
R788
R696
C696 C697
R726
D+5V
IC9001
(U-P)
Pin72
DC PROT
DC DT
OL DT
Q696
Q697
IC601(1/2)
R628
IC603(3/3)
R694
IC601(2/2)
R674
IC603(1/3)
R623
IC603(2/3)
7pin
FR
SL
SR
C
R785
R786
D777
R784
R445
Fan Stop DET.
D+5V
+24V
R727
R438
FL
Q505
D778
MAIN ASSY
IC9001
(U-P)
Pin73
OL DET
Normal : +5 V
OVER LOAD
Detect : 0 V
POWER PACK ASSY
XPROTECT
MAIN ASSY
IC9001
(U-P)
Pin 89
XPROTECT
Normal : +5 V
FAN abnormal
STOP : 0 V
SPEAKER Impedance
Fan Stop
Fan
Fan -
Fan +
Q253
Q252
D+5V
R725
C
C
C
A
A
A