Pwm Modulation Part - LG FA162 Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE OF AUDIO PART

4. PWM MODULATION PART

PWM modulation
part check
Check
IC104 Pin3: 3.3V
If it is YES, then OK. If it is NO, then check
IC104 Pin2: 3.7VA --> IF it is NO, refer to
SMPS troubleshooting.
YES
Check IC602 TAS5548 VDD
power(pin9, 14, 35, 50).
YES
Check
if X600 12.288 MHz is
working.
YES
Check
IC602 TAS5548 Pin11 CLK
input.
YES
Check output
of IC101 LC87FC096AVU
Pin32: PWM_CLK, Pin31: PWM_DATA
Pin19: PWM_RESET
YES
Check
IC602 TAS5548 input
Pin20 -> DATA, Pin21 -> CLK
Pin16 -> RESET
YES
Check PWM
modulator output FL49(+) 48(-),
FR47(+) 46(-).
YES
OK
NO
Refer to
SMPS troubleshooting.
NO
Check the related part of X600.
NO
Replace the related part.
NO
Check resitance output of line
DATA: R610, CLK: R611.
NO
Replace the related part.
NO
Check IC602 TAS5548.
3-9
NO
Replace the related part.
NO
Replace the related part.