Panasonic TH-37PX60U, Technical Manual

Page: 35 / 98

TV_SUB_ON (Relay Drive Circuit)
The F_STBY_ON voltage (3.2V) from pin 6 of connector P7 is applied to pin 23 of the power MCU (IC501) on
the P board. When pin 23 goes “high”, pin 12 goes “high” turning on Q502 to trigger the inrush relay RL403.
Approximately 300ms later, pin 11 also goes ”high” turning on Q501 to trigger the main relay RL402.
300ms later, pin 12 goes “low” allowing for only the main relay RL402 to remain on.
RL401 is triggered whenever RL402 or RL403 are triggered.
AC voltage flows through the relays’ contact, the line filter and the bridge rectifier D401 for conversion into
DC.
35