Mitsubishi Electronics WS-48513, WS-65513, WS-48613 manual Switched Supplies Regulator, Regulation

gence Generator, 3DYC and Signal Select circuitry, and to IC2E65. IC2E65 generates 2.5 Volts for 3DYC.

The 12V supply provides power for Tuners and CRT Protect circuitry. It also is the source of four additional DC Supplies:

•9V-1 for the Signal Select circuitry

•5V-DECOD for the NTSC Decoders.

•9V-2 for CRT Drive, MCS, Signal Select and Doubler circuitry.

•5V-DAC for the Convergence DAC circuits.

1)Closing relay K9A50, shorting out current limiting resistor R9A02, refer to Figure 3-2.

2)Activating a Photo Coupler in PC9A50.

The Photo Coupler turns Q9A56 On, and start up volt- age from the Standby Regulator is applied to pin 4 of IC9A50.

Signal from pin 3 of T9A50 is rectified by D9A44 and added to the start up voltage to maintain oscillation.

Switched Supplies Regulator

Figure 3-9shows the Switched Supplies Regulator. When the TV is switched On, both the PON-1 and PON-2 lines go High. When PON-2 goes High Q9A51 conducts:

Regulation

Regulation is achieved by monitoring the 110V second- ary supply, and through IC9A51 and PC9A50 a cor- rection voltage is fed back to pin 1 of IC9A50. The voltage at pin 1 determines the PWM (duty cycle) of

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