LG 50PC1DR - - 50" Plasma TV, Training Manual

Page: 58 / 138

TROUBLESHOOTING
Plasma Training
58
Troubleshooting
Scan (Y)
Common
sustain (Z)
Data (X)
180 V
( Vs )
180 V
230 V
110 V
65 V
180 V
180 V
Setup Scan ( Address ) Sustain Erase
Set down Set up
170 V
0 V
(GND)
0 V
(GND)
0 V
(GND)
1 sub-field
1 2
3 4 5 6
7 8
9
Video image generation
1. Increase the amount of wall charge by gradually increasing voltage.
2. Decrease created wall charge to certain amount by gradually decreasing voltage.
3. Prepare for scan to keep certain amount of wall charges.
4. Another line is scanning nothing happens.
5. Current line is scanning voltage obtained is X electrode and wall charge on Y electrode conflicts and
discharge occurs.
6. Wall charge increased by scan step.
7. Voltage obtained on Y electrode and wall charge in Z electrode conflicts and discharge occurs.
8. Voltage obtained on Y electrode and wall charge in Z electrode conflicts and discharge occurs.
9. Remove all wall charges by gradually increasing voltage.
Y-Sustain PCB testpoints:
VSET_UP
VSET_DN
+VSC
-VY
RAMP_UP
Scope TP
DC TPoint
Ground
This test point is the
reference for all the following
signals referred to here.
Readings are taken with the
probe set to 10x1.