Abstract: A zero-voltage-switching (ZVS) piezoelectric driving circuit, suitable for use in a switching type power converter. It receives an input DC voltage from a half-bridge driving circuit, and through switching of an high-side switch set and a low-side switch set of the half-bridge driving circuit, converts it to an AC voltage and provides it to a piezoelectric element to drive a load. Wherein, a shunt circuit is connected electrically between the half-bridge driving circuit and the piezoelectric element for zero-voltage-switching (ZVS). Namely, when the high-side switch set and the low-side switch set are both switched off, the shunt circuit resonates with its parasitic capacitance, so that the high-side switch set and the low-side switch set perform ZVS, thus realizing ZVS in a wide range of frequency and a large range of load.

Abstract: A piezoelectric resonant LED driving circuit, wherein a rectifier is used to rectify an AC voltage provided by the supply main into a DC voltage. Then, a quasi-resonant switching module performs resonance by means of the DC voltage to produce an induced current, to raise resonance frequency to operation frequency of a piezoelectric oscillator. Finally, the piezoelectric oscillator performs resonance and filtering using the induced current, to generate a sine wave current. Then, the sine wave current is rectified to output a DC current to drive an LED module.