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3-23
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the MIC IN function, repair the set according to the following guide.
10-5. MIC IN FUNCTION
10-5-1. Solution
Replace IC200, IC206 on MAIN board.
10-5-2. How to troubleshoot (Countermeasure)
1) Check MIC_SIG signal to pin33 of CN605.
If no signal, Check the signal to pin33 of CN315 on the FRONT board.
Check if the signal is entered from pin6 of CN605 to MAIN board.
2) Check if MIC_SIG is entered from pin33 of CN605 to pin3 to IC200 (MIC AMP).
3) Check if the amplified signal comes out from pin4 of IC200.
If no signal output, check +12 V for IC200, replace IC200 with a new one if it has a problem.
4) Check if MCS_BCK, MCS_MLCK & MCS_LRCK is entered from IC501 to IC206.
Check if MIC_DATA_IN is entered from pin9 of IC206 to pin T1of IC501.
If no signal, check +5 V & +3.3 V for IC206. If it is abnormal, change replace it a new one.
5) Check the following I2S signal flow from IC206 to IC501.
If there is any trouble, check the power for each IC. If the signals are abnormal, replace it a new one.
6) Check if the digital audio AMP block is okay.
If AMP is damaged, replace it with a new one.
10-5-3. Service hint (Any picture / Remark)
IC501
MLC3730
IC202
PS9860
PWM
MCS_BCK
MCS_LRCK
IC206
PCM1808
MIC IN
ADC/MIC_DATA
MCS_MCLK
MIC
Board
MIG_SIG
IC200
S4308
IR AMP
IRF6775
MIX_DATA_OUT
< MIC IN function signal
fl
ow >
< MAIN board top view >
IC206
IC206
MCS_MCLK. pin6
MCS_MCLK. pin6
MCS_LRCK. pin7
MCS_LRCK. pin7
MCS_BCK. pin8
MCS_BCK. pin8
MIC_DATA_IN. pin9
MIC_DATA_IN. pin9
MIC_OUTPUT. pin14
MIC_OUTPUT. pin14
Summary of Contents for CM9750
Page 15: ...2 2 ...
Page 19: ...4 SPEAKER SECTION A60L A60R ...
Page 75: ...3 71 3 72 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Page 77: ...3 75 3 76 2 MAIN P C BOARD TOP VIEW ...
Page 78: ...3 77 3 78 MAIN P C BOARD BOTTOM VIEW ...
Page 79: ...3 79 3 80 3 FRONT P C BOARD TOP VIEW ...
Page 80: ...3 81 3 82 FRONT P C BOARD BOTTOM VIEW ...
Page 81: ...3 83 3 84 4 FRONT_CTRL P C BOARD TOP VIEW BOTTOM VIEW ...