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Only for training and service purposes.
ONE POINT REPAIR GUIDE
10. NO SOUND
There is no sound output in the AUX function, repair the set according to the following guide.
10-1. AUX FUNCTION
10-1-1. Solution
Replace IC301 on MAIN board.
10-1-2. How to troubleshoot (Countermeasure)
1) Check AUX_L/R signals to IC301(pin1, 2).
2) Check if DSPI_BCK/ LRCK/ MCLK are entered from IC501 to IC301.
3) Check if ADC_DATA is entered from IC301 to IC501.
If no signal, check DVCC_3.3V & AVCC_3.3V(ADC) for IC301. If is NG, replace it a new one.
4) Check the following I2S signal flow from IC501 to IC601.
If there is any trouble, check the power for each IC. The power is normal but, if the signal waveform to
the IC is distorted or no signal, replace it with a new one.
5) Check if the digital audio AMP block is okay.
If AMP is damaged, replace it with a new one.
10-1-3. Service hint (Any picture / Remark)
AUX
IC501
IC601
PWM
MCS_BCK
MCS_LRCK
IC301
ADC_DATA
DSPI_MCLK
AUX_L/R
IR AMP
MIX_DATA_OUT
< AUX function signal
fl
ow >
< MAIN board bottom view >
IC301
IC301
IC601
IC601
DSPI_MCLK(R321)
DSPI_MCLK(R321)
DSPI_LRCK(R320)
DSPI_LRCK(R320)
DSPI_BCK(R319)
DSPI_BCK(R319)
ADC_DATA_IN(R312)
ADC_DATA_IN(R312)