Panasonic TH-37PX50U Technical Manual page 16

The DC voltage from the rectifier is converted to 395Vdc by the "Power Factor
Control" circuit to improve the power ratio.
This DC voltage is applied to three different circuits; the Vsus, the Vda and the Low
Voltage (F STB 14V, 15V, and 12V) power supplies.
During standby operation, both the Vsus and the Vda power supply circuits are off.
Only the "F STB 14V" section of the Low Voltage power supply circuit is on.
Figure 10
The "F14V ON" command (5V) from pin 10 of MC701 turns on Q452 and the "F STB
14V" is output to the PA-board through pins 1, 2, and 3 of connector P10.
(See Fig. 10)
Note: The above description is true for standby mode only; the power has not been
turned on yet.
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