3-15
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.
5-5. IN THE TUNER FUNCTION
5-5-1. Solution
Please check and replace IC202 and IC200 on MAIN board.
5-5-2. How to troubleshoot (Countermeasure)
1) Check if TUNER_LR is entered from pin14. 13 of IC 200 to IC202(Pin29, 30).
If no signals, check AVCC_3.3V for IC200 power.
Check if the tuner control signals (CLK, DAT, CE, RST, SLT) are entered from IC500 to IC200.
If it doesn’t work, replace IC200 with a new one.
2) Check if MCS_BCK, MCS_LRCK, & MCS_MCLK are entered from IC500 to IC202.
3) Check if ADC_DATA_IN is entered from IC202 to IC500.
If no signal, check AVCC_3.3V & DVCC_3.3V for IC202. If is NG, replace it with a new one.
4) Check the following I2S audio signal flow from IC500 to IC700.
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.
5-5-3. Service hint (Any picture / Remark)
< TUNER IN function signal
fl
ow >
II C501
Mai n DSP
( +3. 3V_CD, VCC1. 2)
P
W
M
_
L
R
C
K
/
B
C
K
/
D
A
T
A
FRONT( BTL)
SW(PBTL)
[CK57 : Total 2.1ch 1100W
350+350+400]
[CK56 : Total 2ch 700W]
LPF
AMP
I c701
PW
M
I C700
FRONT( BTL)
PWM + AMP Bl ock
AMP
I C702
CK57 Only
LPF
I C202
TUNER
( FM/ AM)
FM/AM
< MAIN board top view >
IC202
IC202
TUNER_R/ TUNER_L
TUNER_R/ TUNER_L
ADC_D/ ATA_IN
ADC_D/ ATA_IN
BCK
BCK
LRCK
LRCK
Содержание CK57
Страница 13: ...1 12 Copyright 2018 LG Electronics Inc All rights reserved Only for training and service purposes ...
Страница 15: ...2 2 Copyright 2018 LG Electronics Inc All rights reserved Only for training and service purposes ...
Страница 17: ...Copyright 2018 LG Electronics Inc All rights reserved Only for training and service purposes 2 6 2 5 ...