| 摘要 |
A power circuit for use in a TV receiver having a satellite broadcast receiving function or a teletext receiving function is disclosed. The power circuit comprises a main power source for supplying a large power to the mai n load, i.e., the signal-reception, signal-processing, and display circuits of the TV receiver, and a sub-power source for supplying power to small-power drawing circuits such as a satellite broadcast receiving tuner, a UHF/VHF tuner, a teletext receiving circuit, a microprocessor, and a remote control receiving circuit. In order to activate the main load while power is being supplied fr om the sub-power source to the sub-load, a switch circuit is turned ON and, thereby, the main power source is supplied to the main load. A circuit is provided fo r restricting current flowing into an output-voltage-detection and error- amplifier circuit connected with the sub-power source, thereby raising the output voltage from the sub-power source to the sub-load, immediately before the microprocessor renders the switch circuit conductive. Thus, the voltage drop occurring in the sub-power source when power is started to be supplied to th e main load is avoided.
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