47
VSX-LX52
5
6
7
8
5
6
7
8
A
B
C
D
E
F
[2] Protection Circuit Process List (XPROTECT)
XPROTECT Circuit
Item
Purpose
Detection Method
Process
Warning Indication
Remarks
XPROTECT
AMP power supply circuit and
Transformer short circuit
detect. (defect status)
Observe C
N
5701 pin3 or pin5
voltage,
V
L+ and
V
L-.
Detects when the XPROTECT
port becomes "L".
(Pin
8
3 of IC3001)
Turns muting on and
speaker relay off, and
immediately turns off the
power. Then flashes
MCACC indicator.
N
one
Once detected and turned
the power off, the power
cannot be turned on again.
(*)
(*) To restore the previous status, follow the procedure
described in “How to Enter Release Mode” (P.49)
then turn the unit back on.
COMPONENT ASSY
D
POWER AMP ASSY
H
DISPLAY ASSY
J
UCOM
IC3001
8
3
R5723
47k
R5725
47k
R5726
47k
R5727
220k
R572
8
220k
D5721
1SS352
D5722
1SS352
10u/63
C5723
TS
GAMP
D57
8
2
UDZS7R5(B)
LTC124EUB
Q57
8
1
LTC124EUB
Q57
8
2
LTA124EUB
Q57
8
3
LTA124EUB
Q57
8
4
D57
8
3
1SS352
D57
8
4
1SS352
D57
8
1
UDZS5R1(B)
C57
8
1
0.01u/50
G
N
DU
R57
8
1
1k
V
+5_UST
Short circuit detect:
AMP power supply circuit (VL)
Short circuit detect:
Transformer
R57
8
2
10k
R57
8
3
10k
V
L+
V
L-
G
N
DU
V
+5_UST
R57
8
4
47k
LTC124EUB
Q57
8
5
G
N
DU
R57
8
5
100k
R5724
47k
C57
8
2
1u/10
C
N
5701
-5
C
N
5
8
05
-5
C
N8
014
-5
C
N8
005
-15
C
N
3001
-12
C
N
5701
-3
G
N
DU
R3060
1M
C3016
0.047u/50
DIGITAL MAIN ASSY
E
C
N
1250
-4
C
N
1401
-2
8
V
+5_UST
V
+5_ST
R57
8
6
10k
D3005
D3004