76
November 2009 50PQ30 Plasma
Using the “Diode Test” on the DVM, check
the pins for shorts or abnormal loads.
Y
Y
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Drive Buffer Troubleshooting
Drive Buffer Troubleshooting
RED LEAD ON
BUFFER IC FGnd
BLACK LEAD ON “ANY”
OUTPUT LUG.
READING 0.798 V
BLACK LEAD ON
BUFFER IC FGnd
RED LEAD ON “ANY”
OUTPUT LUG.
READING “OPEN”
YOU CAN CHECK ALL 8 BUFFER ICs USING THIS PROCEDURE
YOU CAN CHECK ALL 8 BUFFER ICs USING THIS PROCEDURE
•
Any of these output lugs can be tested.
•
Look for shorts indicating a defective Buffer IC
Indicated by white outline
Indicated by white outline
128 Output Pins per/FPC (Flexible Printed Circuit)
6 Ribbon cables (Horizontal Electrodes)
768 Total Horizontal Electrodes controlling Vertical resolution
BUFFER IC FLOATING GROUND (FGnd)
BACK SIDE OF Y-DRIVE BOARD
128
Output
Pins
42 43 43