4-6
6. PWM MODULATION PART
Check P7905 9PIN 3.3V
Check if X601 12.288MHz is
working.
Check IC604 PS9829
86 PIN CLK input
Check output of IC100
78KOKF2
21
➞
PWM_CLK
22
➞
PWM_DATA
43
➞
PWM_REST
Check IC604 PS9829 DATA
input
78 PIN
➞
DATA
79 PIN
➞
CLK
96 PIN
➞
REST
Check PWM MODULATOR
output
FL:75(+)74(-) FR:71(+)70(-)
OK
Check IC604 PS9829 VDD
PIN power (3,10,22,29,39,47,
56,65,72,87,94) Check X601
2PIN 3.3V
Refer to SMPS
Troubleshooting
Check the related part of
X601
OK
Check R668(470Ω) output
OK
Check resistance output of
LINE
DATA: R671
CLK: R670
RST: R665
OK
Check DVD ASS`Y PS9829
communication condition (P7403)
Check IC604 PS9829 DATA input
OK
Check IC604 PS9829 part.
Replace the related
part
Replace the related
part
Replace the related
part
Refer to DVD
Troubleshooting
Check resistance
output of each LINE
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
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