Panasonic TH-37PX60U, Technical Manual

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TV_SUB_ON (F_STB_ON)
The F-STB-ON voltage (3.2V) from pin 6 of connector P7 is applied to pin 23 of the Power CPU (IC501) on
the P board. IC501 sends out commands to first turn on the primary circuit of the power supply, and then the
circuit that allows the F_STB15V to develop.
1. The relay commands (high) from pins 11 and 12 of IC501 are used to trigger the relays RL402 and
RL403.
2. A low from pin 16 of IC501 is used to turn on the power factor control IC (IC406) to generate the 395V
DC.
3. A high from pin 15 of IC501 is used to turn on the V-low power control IC (IC520) to turn on the oscillator
in the “Active Clamp Full Bridge System” circuit.
4. A low from pin 18 of IC501 is used to turn on the F_STB15V DC/DC converter Q556.
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