OUT4
1
OUT3
2
OUT2
3
OUT1
4
AVDD
5
SWIN
6
GNDS
7
SRIN
8
SLIN
9
GNDC
10
CIN
11
GNDR
12
RIN
13
GNDL
14
LIN
15
BYPASR
16
BYPASL
17
LTRE
18
LBASS3
19
LBASS2
20
LBASS1
21
RBASS1
22
RBASS2
23
RBASS3
24
RTRE
25
CR2
26
CR1
27
CL2
28
CL1
29
AVSS
30
LOUT
31
ROUT
32
COUT
33
SLOUT
34
SROUT
35
SWOUT
36
AGND
37
DGND
38
LATCH
39
DATA
40
CLK
41
DVDD
42
N104
M62446
C112
4.7u/16V
C115
4.7u/16V
C117
4.7u/16V
C120
4.7u/16V
C122
4.7u/16V
C124
4.7u/16V
C126
822
C127
15n
C128
0.33u
C109
47n
C111
47n
R141100
C113
4.7u/16V
C114
4.7u/16V
C116
4.7u/16V
C118
4.7u/16V
C119
10u/16V
C121
10u/16V
C123
4.7u/16V
C125
4.7u/16V
C139
822
C140
15n
C141
0.33u
C13747n
L103100uH
+5VD
C133
47u/16V
A-6.8V
A-6.8V
C110
47u/16V
C138
47u/16V
R136
22K
4052_B
4052_A
4053_INT
R135
22K
R134
22K
R127
22K
C134
101
C135
101
A+6.8V
5.1CH
A+6.8V
X0
12
X1
13
Y0
2
Y1
1
Z0
5
Z1
3
INH
6
A
11
B
10
C
9
VEE
7
Z
4
Y
15
X
14
VDD
16
Vss
8
N102
CD4053
A+6.8V
A-6.8V
TUNER_R
CD-R
DVD-R
TUNER_L
CD-L
DVD-L
SR-1
SL-1
C-1
R-1
L-1
A
B
INT
5.1CH
A
B
C
X0
12
X1
14
X2
15
X3
11
Y0
1
Y1
5
Y2
2
Y3
4
INH
6
A
10
B
9
VEE
7
X
13
Y
3
VDD
16
VSS
8
N101
CD4052
FL
FR
L-1
R-1
SL-1
SR-1
C-1
SW-1
SW-1
CLK
DATA
LAT
CLK
DATA
LAT
4052_B
4052_A
C107
10u/16V
C108
10u/16V
4053_INT
A
B
X0
12
X1
14
X2
15
X3
11
Y0
1
Y1
5
Y2
2
Y3
4
INH
6
A
10
B
9
VEE
7
X
13
Y
3
VDD
16
VSS
8
N111
CD4052
A-6.8V
A+6.8V
R1494K7
R1504K7
INT
2. Causes of power-on protection: over-current protection, over-voltage protection and CPU cannot
detect RLY0 signal; test whether each output channel has DC output; when power-on protection trouble
appears, make clear which reason caused it. Centre or surround power IC have trouble, which cause
that output signal has DC in it.
Example 2 Symtopm: no sound output
Description: power on, after system resets normally, switch each sound source and there is no
output, select decode and there is no output.
Analysis and troubleshooting: after power on, select VCD channel, input sine wave signal, shown
as in the figure 3.3.1.2; test volume board capacitor C119, C121 and there is no signal, test signal board
capacitor C122, C124 and there is still no signal, pin 4, 11 of N101 has signal, test power voltage of pin
7, 16 of N101 and it is normal, pin 3, 13 of N101 has no signal, so we preliminarily judge that N101 has
input but has no output, we judge that N101 has no trouble, test pin 9 of N111 and it is high level, we
judge that this channel is not gated, signal A, B of N104 has trouble. Change N104, after changing,
output is normal and trouble is removed.
[
]
Figure 3.3.1.2 Volume circuit diagram
Note: when there is no output, firstly make sure that it is a certain channel has no output or all
channels have no output; that all channels have no output may be caused by abnormal power supply of
a certain part, or abnormal mute signal; then make clear whether it is decode has no output or signals
without being decoded have no output; that decode has no output is caused by abnormal working of
decode part, please refer to cases of “decode has no output”. CD4052 and CD4053 belong to electronic
switch with high switch frequency easy to damage and may pull down +6.8V and -6.8V voltage after
damage, or pull down the gating signals A, B of 62446, and trouble of no output appears.
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