3-20
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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.
6-7. MIC IN function
6-7-1. Solution
Replace IC206 on MAIN board, ICA301 on MIC & RMC board.
6-7-2. How to troubleshoot (Countermeasure)
1) Check MIC_SI & MIC_S2 signal to pin6, 8 of CN301.
If no signal, Check the signals to pin6 & 8 of CNA301 on the MIC & RMC board.
Check if the signal is entered from pin6 & 8 of CNA301 to pin6, 8 of CN301.
2) Check if MIC_SIG is entered from pin2 of JK302 & JKA303 to pin2, 13 to ICA301 (PRE AMP).
3) 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.
4) Check if DSPI_BCK, LRCK,MCLK are entered from IC501 to IC301.
Check if MIC_DATA_IN is entered from pin19 of IC301 to pin H2 of IC501.
If no signal, check AVCC_3.3V & DVCC_3.3V 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 on item 6-1.
If AMP is damaged, replace it with a new one.
6-7-3. Service hint (Any picture/ Remark)
ICA301
ICA301
< MIC & RMC board top view >
Pin15:DSPI_MCLK
Pin15:DSPI_MCLK
Pin16:DSPI_LRCK
Pin16:DSPI_LRCK
Pin17:DSPI_BCK
Pin17:DSPI_BCK
< MAIN board bottom view >
IC301
IC301