摘要 |
A high frequency induction heating appliance comprising a working coil for generating a high frequency signal, a switching device for switching a drive voltage to the working coil, a low voltage transformer for lowering an AC power voltage, an input current detector for detecting current of the AC power, an output adjusting device for providing an output adjusting signal, a differential amplifier for amplifying a difference between output signals from the input current detector and output adjusting device, a first comparator for comparing the output signal from the input current detector with a reference voltage, an integrator for integrating an output signal from the differential amplifier, a start signal generating circuit, a zero crossing detecting circuit, a delay circuit for delaying a zero crossing detect signal by a time period, an AND logic operating circuit for AND logic-operating a start signal and the delayed zero crossing detect signal, a synchronizing signal generator, a reference signal generator, a second comparator for comparing an output signal from the AND logic operating circuit with a reference signal or comparing an output signal from the integrator with the reference signal, and a drive controller for controlling the operation of the switching device in response to an output signal from the second comparator.
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