Sanyo PLC-SW36, Руководство по обслуживанию

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Troubleshooting
Q5006
Q5007
Q5051,52
2,6
1
5
3
8
12 13 141
5
9
Mute: H
Plug-in mute: H
Mute: L
K8F
K50B
K10E
P_SCLK2
MUTE_SW
Monitor mute: H
MUTE_A
V
P_SCDA2
MAIN BOARD
AV
BOARD
IC5003
AMP.
<LM4865M>
IC5001
VOLUME
<BA7655A>
L
R
L
R
AUDIO-OUT
AUDIO-IN
SP901
IC1801
OUTPUT
EXPANDER
<74LCX574>
IC3551
D/A
CONVERTER
<M62393>
IC301
SYSTEM
CONTROL
<PW168A>
+
+
2
+
4
15
13
11
10
8
9
1
3
+
-
Q5007
DATA BUS
7
5
1
7
3
IC5002
AMP.
<LA6358NM>
+
+
+
Q5004
Q5003
MUTE
V
OLUME
Q2004,06
IC1811
BUFFER
<74LCX541>
●
Audio signal processing circuit
●
No Sound
Check Audio control and pre-amp. circuit.
Check IC5001(audio-control IC), IC5002(audio pre-amp IC) and
peripheral circuit.
Check the control voltage on pin 2 and 6 of IC5001.
L: minimum volume, H: maximum volume
Is the audio signal
observed at pins 1 and 7
of IC5002?
Check Audio amp. and control circuit.
Check IC5003(audio-amp IC) and peripheral circuit.
MUTE signal (Mute:L) is applied on pin 4 of IC5003, sent from
pin 12 of IC1801
.
When the mini jack plug is connected to the audio out terminal, the
MUTE_SW signal is applied on pin 4 of IC5003.
L: MUTE ON, H: MUTE OFF
Check 5V_AUD power supply line.
Is the audio signal
observed at pins 5 and
8 of IC5003?
Check audio output circuit.
Check speaker, connection of the terminal “K8F”.
Yes
No
Yes
No
Check following steps.