Panasonic TC-P50VT20 Technical Manual page 61

When IC9400 is turned on, it outputs the STB_D3.3V and the reset pulse to the Panel
CPU (IC9003) on the D board.
When the CPU on the D board is energized, it outputs 2 commands:
• The "PANEL_MAIN_ON"
• The "POWER ON/OFF.
The PANEL MAIN ON command turns on the power supply circuit that outputs the Vsus,
Vda, 15V, and 5V.
The POWER ON/OFF command turns on the Video/Panel Control and the Discharge
Control circuits in the D board.
Power On Operation
Slide 61