Patent ID: 7545105

Claim:
A driving circuit for piezoelectric lamps comprising a power source, a dimming signal source to generate a first reference cycle signal, at least one piezoelectric transformer and a power switch unit to control power amount passing through the piezoelectric transformer through alteration of a duty cycle, and at least one load functioned by receiving the power transformed and output by the piezoelectric transformer, the driving circuit further including: a pulse modulation unit to generate a duty cycle signal of the power switch unit and a buffer unit connecting to the pulse modulation unit, the first reference cycle signal being sent to the buffer unit which generates a second reference cycle signal at a potential lower than the potential of the first reference cycle signal, the potential of the second reference cycle signal output from the buffer unit gradually rising from an initial state to the potential of the first reference cycle signal to form a buffer time series, through potential alteration of the second reference cycle signal and the pulse modulation unit the duty cycle ratio of the duty cycle signal is changed.