Panasonic TH-37PX50U Technical Manual page 14

Instead of a standby power switch, as it shows in the diagram, the TV has a jumper wire
on the "S" board that connects pin 8 of the connector P12 to ground. As a result the
transistors Q553 and Q554 turn on, allowing the STB5V to be applied to the D and the
DG-board via pin 10 of the connector P25. (See Fig. 6).
Figure 7
The Microprocessor on the DG board (IC4005) receives the regulated STB3.3V from
IC4010. Pin 22 of IC4005 outputs 2.5V (Tuner SUB ON) to the P board via pin 14 of the
connectors DG3/D3 and pin 13 of the connector P25/D25. It is then connected to pin 21
(F. STB ON) of the "Power Output Control" IC, MC701. (See Fig. 7 & 8.)
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