Y DRIVE BOARD TROUBLESHOOTING - LG PLASMA TV 50PG20

Y-DRIVE BOARD

Y-Drive Board works as a path supplying the Sustain and Reset waveforms, which are made in the Y-SUSTAIN B/D and sent to the Panel through SCAN DRIVER IC’s. The Y Drive Boards supply a waveform, which selects the horizontal electrodes sequentially.

50PG20 uses 8 DRIVER ICs on 2 Boards (TOP, BOTTOM: 4 each). 50G1 Panel has 768 Vertical lines of resolution (Horizontal Grids determine V Resolution)

4 Ribbons (Tabs) separated into 2 = 192 grids per tab.

8 Ribbon inputs to 4 Tabs = 96 lines per ribbon input

2 Buffers per Ribbon input = 96 lines per ribbon input.

5 Volts (Floating Ground) 5VFG and Logic Signals from Y-SUS Board are supplied to the Top Drive Board on Connector P100.

5 Volts (Floating Ground) 5VFGinput also enters the Bottom Y Drive Board at P200.

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To remove the Ribbon Cable from the connector first carefully lift the Locking Tab from the back and tilt it forward (lift from the outside edge as shown).

Lift up the entire Ribbon Cable gently to release the Tabs on each end. Gently slide the Ribbon Cable free from the connector.

To re-install the Ribbon Cable carefully slide it back into the slot, be sure the Tab is seated securely and press the Locking Tab back to the locked position.

The Ribbon Cable is clearly improperly seated into the connector. You can tell by observing the linearity. Note the cable is crooked. In this case the Tab on the Ribbon cable was improperly seated at the bottom. This can cause bars, lines, and intermittent lines abnormalities in the picture. Remove the ribbon cable and re-seat it correctly.