Driver Reset Circuit Operation - Panasonic TC-P42X1 Technical Manual

Driver Reset Circuit Operation

https://www.werbemousepads.de/pdf/
The DRV RST circuit of the A board is used to monitor the physical connection of the A board to the C
board. DRV RST input to IC9500 and IC9003 must be high for the unit to operate. The A board
provides the 5V source needed to power the C boards. On the C1 board and the C2 board, the 5V is
routed back to the D board via connector C11/A31, C21/A32 to activate the 5V SENSE circuit. A voltage
divider in the C1 board develops a voltage drop that causes the collector of transistors Q9301 to
become low. As a result, the base voltage of Q9302 also becomes low causing its collector to go high.
The output voltage is applied to IC9500 and IC9003 as DVR RST.
When the 5V SENSE circuit does not detect 5V from the C1 board and the C2 board, the DVR RST
output becomes low. The unit goes into shutdown and the power LED blinks 6 times.