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Figure 5-34 Y output voltage waveform
No Specified Brightness at Specified Colour
1. Check the connector of the CTRL board input signal
(LVDS).
2. Replace the CTRL board.
5.2.3
Checking for Component Damage
Y IPM (IC 18) or Z IPM (IC 2)
When the internal Sustain FET or ER FET of the Y IPM (IC18)
or Z IPM (IC2) is damaged, there will be no picture, or the
screen is partially mis-discharged.
•
Test Points: Waveform-GND (Y-DRV board), B28-GND (Z
board).
•
Wave format: Waveform (Y-DRV board) or B28 (Z board)
has no output wave.
Figure 5-35 IPM normal output
FET assy (Y board: HS2)
When the Set_up FET (2nd FFT of HS2) is damaged, there will
be no picture.
•
Test Point: GND-Waveform (Y-DRV board)
•
Measuring condition: full white pattern.
•
Wave format: as shown in the figure below.
Service Modes, Error Codes, and Fault Finding
G_16391_008.eps
020707
G_16390_049.eps
150806
LGE PDP 2K6
Set up waveform
does not come out
Figure 5-36 Set_up FET defective
When the Set_down FET/Pass_Top FET(1st, 3rd, 4th, 5th FFT
of HS2) is damaged, mis-discharge of the entire screen is
generated.
•
Test Point: GND-Waveform (Y-DRV board)
•
Wave format: as shown in the figure below.
Set up waveform
does not come out
Figure 5-37 Set_down FET defective
SCAN IC (Y-DRV board: IC1-10)
1. In case of the SCAN IC is damaged, one horizontal line
may be open on the screen.
–
Test Point: ICT output - GND on the Y DRV board.
–
Wave format: As shown below figure.
2. When the SCAN IC is damaged (poor, external electricity,
or spark), there might be no picture.
–
Test Point: ICT output - GND on the Y DRV board.
–
Wave format: Output wave format is not generated
(you can see if which SCAN IC is damaged).
3. Overlap of two horizontal lines on the screen in case of
shorted SCAN IC output.
–
Test Point: ICT output - GND on the Y DRV board.
–
Wave format: As shown in figures "SCAN IC shorted
output" and "SCAN IC normal output".
5.
EN 21
G_16390_050.eps
150806
G_16390_051.eps
150806
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