LG FA163 - PWM MODULATION AND POWER AMP TROUBLESHOOTING

3-27
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
8. PWM MODULATION PART CHECK
PN102 PIN9,10
3.3V Check
PWM MODULATION
PART CHECK
Refer to SMPS
Troubleshooting
NO
NO
NO
Check
X701 12.288MHz
Operation.
IC702
PIN86 CLK INPUT
Check
Check
IC100(LC87Fxx)
PIN22:PWM REST
PIN79:PWM SDA
PIN80:PWM SCL
OUTPUT
YES
YES
YES
YES
YES
YES
YES
YES
Check
IC702(PS9830)
DATA INPUT PIN23,24,25,26
PWM WAVE
Check.
Check PWM
Modulator output
FL:PIN75(+),74(-)
FR:PIN71(+),70(-)
OTHER OUTPUT
Check
Check IC604(PS9830)
VDD PIN VOLTAGE
(3,10,22,29,39,47,56,65,72,87,94)
Check X701 PIN2 :3.3V
OK
Replace X701.
NO
YES
Check X701
12.288MHz
OK
Replace R797,R795,R790
NO
YES
Check LINE
Resistor output
SDA:R797,SCL:R795
RST:R790
Refer to cD troubleshooting
NO
Check
CD ASSY Communication
Check each LINE
Resistor output
NO
Check
IC702(PS9830) DATA
INPUT
OK
YES
YES
OK
Replace IC702.
NO
Check
IC702(PS9830)
YES
OK
NO
NO
jomi