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Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the TUNER function, repair the set according to the following guide.
10-3. TUNER FUNCTION
10-3-1. Solution
Replace IC301, IC302 on MAIN board.
10-3-2. How to troubleshoot (Countermeasure)
1) Check if TUNER_LR is entered from pin13 &14 of IC302 to IC301(pin27, 28).
If no signals, check AVCC_3.3V for Tuner power.
Check if the Tuner control signals (CLK, DAT, CE, RST) are entered from IC501 to IC302.
If it doesn’t work, replace IC302 with a new one.
2) Check if DSPI_BCK, DSPI_LRCK & DSPI_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 audio 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. Refer to “Digital Audio AMP” guide.
If AMP is damaged, replace it with a new one.
10-3-3. Service hint (Any picture / Remark)
T-
IC501
IC601
PWM
MCS_BCK
MCS_LRCK
IC301
ADC_DATA
DSPI_MCLK
TUNER_L/R
IR AMP
IC302
TUNER
MIX_DATA_OUT
< TUNER function signal
fl
ow >
< MAIN board bottom view >
IC301
IC301
IC601
IC601
TUNER_L to pin27
TUNER_L to pin27
TUNER_R to pin28
TUNER_R to pin28
Содержание OK99
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