3-15
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the OPTICAL function, repair the set according to the following guide.
5-6. OPTICAL FUNCTION
5-6-1. Solution
Replace MAIN board.
5-6-2. How to troubleshoot (Countermeasure)
1) Check DSPI_BCK, LRCK, MCLK, ADATA of IC304(pin27, 28, 29, 31).
If no signal, check the signal from JK303 pin1 to IC304 pin1
and cable connection state.
If there are no signal out from JK303, replace new connector and cable.
2) Check if MCS_BCK, MCS_LRCK & MIX_DATA IN is entered from IC501 to IC601.
If no signal, check +3.3 VA & +1.2 VA for IC501.
If it is abnormal, change replace it a new one.
3) Check the following I2S signal flow from IC501 to IC601.
If there is any trouble, check the power for each IC.
If the signals are abnormal, replace it a new one.
4) Check if the digital audio AMP block is okay. Refer to “Digital Audio AMP” guide on item 6-1.
If AMP is damaged, replace it with a new one.
5-6-3. Service hint (Any picture/ Remark)
IC501
IC601
PWM
MCS_BCK
MCS_LRCK
MIX_DATA_OUT
AMP
JK303
IC304
DSPI_MCLK
DSPI_LRCK
DSPI_BCK
DSPI_ADATA
< OPTICAL function signal fl ow >
R611
R613
4
R616
R617
R626
R627
R628
R629
R247
R248
R250
C601
3
C605
C615
R5E9
R712A
ZD702
L306
L308
Q706
Q
C2C11
L329
R710
R328
R329
R712
R330
L
R348
R355
R358
R359
R360
R361
R362
R363
R365
R366
R367
C713
R
R755
R757
R758
C336
C337
C721
R380
R382
C348 C349
C351
C353
C359
Q207
Q208
C376
C378
C381
IC303
IC304
C386
C387
C388
C390
C391
C393
01
C399
C788
< MAIN board top view >
IC304
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