Service manual

CONFIDENTIAL – DO NOT COPY
Page10-10
File No. SG-0174
6
Check U45
H sync output Î U45 pin4,R181
V sync output Î U45 pin8,R184
Is there signal?
No
Is picture on screen?
No
Check U45
H sync input Î U45 pin1,R185
V sync input Î U45 pin5,R187
Check U22’s signal output
R signal ÎC233,R180,R169,U22.34
G signal ÎC232,R177,R171,U22.31
B signal ÎC231,R174,R176,U22.28
Yes
No
Check U22 input signal
R Î pin 2, C239;C241(AC coupled),R186,R172(75ohm)
G Î Pin 4,C234;C236(AC coupled),R166,R175(75ohm)
B Î Pin 6,C221;C224(AC coupled),R164,R173(75ohm)
PDP DISPLAY NOTHING(RGB on PIP mode without screen)
BLOCK 1
Check U45
pin 14Î +3.3V
Yes
Check input source
No
U45 fail
Yes
Check U22
Input clamp voltageÎpin 1(+5V_V1)
Output clamp voltageÎpin 35(+5V)
VCC3Îpin 22,23(+5V)
Input_switch_selectÎlow (0V)
Yes
U22 fail
No