Power supply apparatus, and image forming apparatus having the same

Abstract

In a power supply apparatus including a plurality of power supply circuits, each of the power supply circuits has a piezoelectric transformer, a rectification element which rectifies and smoothes a voltage output from the piezoelectric transformer in accordance with a load and outputs the voltage, a voltage-controlled oscillator which controls the frequency of an output signal in accordance with an input control signal, and a power supply voltage supply element which is driven by a signal output from the voltage-controlled oscillator and supplies a power supply voltage to the piezoelectric transformer. One power supply circuit includes a resonance frequency change unit which is connected to the output side of the piezoelectric transformer. The resonance frequency change unit drives the piezoelectric transformer of the power supply circuit at a driving frequency which is different from the driving frequency of the piezoelectric transformer in another power supply circuit by shifting the peak of the resonance frequency.

Dependencies are inferred from the claim text.