Signal Process Start-Up Circuit - Panasonic TC-P54Z1 Technical Manual

Signal Process Start-up Circuit

The power MPU IC701 on the P-Multi board receives STB5V when the unit is plugged in to the AC
line.
When the display's main switch is turned on, the voltage at pin 25 of the power MPU (IC701) changes
from 4.7V to 0V. This turns on Q551 and STB5V is output to the A board via connectors P7 (Pin 3).
The STB5V from pin 3 of connector P7 is connected to pin 6 of connector A6.
STB5V is applied to a 3.3V regulator (IC25480) to power the Main MPU (IC21100) on the DA board.
This energizes the microprocessor (CPU) and gets it ready for program execution.
The 3.3V from the voltage regulator besides being applied to the CPU, is also applied to the power
LED on the K board through pin 4 of connector DA1/KA1.(Not shown here).
If the STB5V is missing, the TV is dead (No power).
The system MPU (IC21100) outputs a 3.2V command (TV-Sub-On/F-STB-On) to the power supply
through pin 5 of connector P7.
This command forces pin 39 of IC701 on the power supply to go low. This in term forces pins 15, 16,
10, and 11 to go low.
When pins 15 and 16 go low, the In-rush and Main relays are triggered allowing AC to be applied to a
bridge rectifier.
The DC voltage from the rectifier is applied to the Vda/P15V Power Factor Control circuit.
The changes on pins 10 and 11 turn on the Power Factor Control circuit and the Vda/P15V Control
circuit and F+15V is output from MC302.
The F+15V is connected to pins 23, 25, and 27 of connector DA6 on the DA board.
F+15V is the source of a DC-DC converter circuit in the DA board composed of IC25600, IC25601,
IC25300, and IC25312. This circuit outputs SUB5V, SUB3.3V, SUB1.8V, SUB1.2V, GC6-3.3V, GC6-
1.8V, GC6-1.2V respectively.
SUB5V and SUB3.3V are connected to the MPU (IC21100) for voltage output confirmation.
Slide #44