User manual

The microprocessor (IC9709) on the D-board sends a “High” on its pin 45 to the P-
Board via pin 2 of connector D27/P27. The relay driver Q401 activates the relay,
supplying AC to D451/IC451. The resulting 380VDC is used to power the switching
regulator of IC552/T502. This circuit supplies 5V, 12V, 15V, and the Vda voltage. It also
supplies 21V. This voltage is applied the15V regulator, IC550. The 15V is used as the
start-up voltage for the sustain power supply (T501 and IC551), which also utilizes the
380V to start its oscillation to generate the sustain voltage (Vsus)
TH-42PD25U-P Power-On with Remote Control
The sensor receiver on the K-board receives the infrared signal from the remote control.
The signal is amplified and routed through the C2-board. Then it is applied to pin 40 of
the microprocessor (IC9709). The remote control signal is also applied to pin 72 of
IC001 via IC9709, pin 25 of connector D3, and pin 15 of connector DG3. The
microprocessor IC001 sends a “High” on pin 53, repeating the process mentioned
above.
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