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Only for training and service purposes.
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the MIC IN function, repair the set according to the following guide.
10-4. MIC IN FUNCTION
10-4-1. Solution
Replace ICA301 on FRONT board, IC501 on MAIN board.
10-4-2. How to troubleshoot (Countermeasure)
1) Check MIC_S1 & MIC_S2 signal to pin6 & 8 of CN301.
If no signal, check the signals to pin6 & 8 of CNA301 on the JACK board.
Check if the signal is entered from pin 5 & 6 of CNA301 to CN301.
2) Check if the amplified signal comes out from pin3 & 12 of ICA301.
If no signal output, check DVCC_3.3V for ICA301, replace ICA301 with a new one if it has a problem.
3) Check if DSPI_BCK, DSPI_MLCK & DSPI_LRCK is entered from IC501 to IC301.
4) Check if MIC_DATA is entered from IC301 to IC501.
If no signal, check DVCC_3.3V & AVCC_3.3V(ADC) for IC301.
If it is abnormal, change replace it a new one.
5) Check the following I2S signal flow from IC301 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. Refer to “Digital Audio AMP” guide.
If AMP is damaged, replace it with a new one.
10-4-3. Service hint (Any picture / Remark)
T-
IC501
IC601
PWM
MCS_BCK
MCS_LRCK
T
IC301
MIC_DATA
DSPI_MCLK
MIC_S1,2
IR AMP
ICA301
Preamp
MIX_DATA_OUT
Mic
1, 2
< MIC IN function signal
fl
ow >
< MAIN board bottom view >
IC301
IC301
MIC_S2 to pin4
MIC_S2 to pin4
MIC_S1 to pin3
MIC_S1 to pin3