Pioneer VSX-917V-K Service Manual page 132

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4. XPROTECT Detection Circuit Diagram
When below 6 kind of voltage supply become to
A
be short circuit to GND, XPROTECT circuit work
and U-P input port voltage change from +5 V to 0 V.
The U-P detect this condition as ERROR.
• Voltage supply to POWER AMP IC (V neck+)
• Voltage supply to POWER AMP IC (V neck-)
• Voltage supply to POWER AMP IC (VL+)
• Voltage supply to POWER AMP IC (VL-)
• Voltage supply to +12 V REGULATOR IC
• Voltage supply to -12 V REGULATOR IC
B
A MAIN ASSY
XPROTECT
C
D
E
F
132
1
2
IC9001
(U-P)
89
2
3
Voltage supply
to POWER AMP IC
(V neck+)
R713
D713
1k
1SS133
D+5V
R697
10k
Q698
R698
33k
Voltage supply
to POWER AMP IC
(V neck-)
Voltage supply
to POWER AMP IC
(VL+)
D+5V
D+5V
D703
Q705(1/2)
R727
10k
R715
R714
10k
1k
Q705(2/2)
R716
C709
1/50 10k
Voltage supply
to POWER AMP IC
(VL-)
Voltage supply
to +12 V
REGULATOR IC
D+5.6V
D807
Q807(2/2)
R807
R808
10k
1k
Q808(2/2)
C806 R806
1/50 10k
Voltage supply
to -12 V
REGULATOR IC
VSX-917V-K
3
4
Q701
2SC5511(E)
C
POWER PACK ASSY
Q702
2SA2005(E)
Q707(1/2) C703
3300 D702
/42 D5SBA20(B)
Q707(2/2)
C704
3300
/42
Q807(1/2) C801
2200
D801
/25
S1WB(A)60SD
Q808(1/2)
C802
2200
/25
D806
MTZJ6.2B
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