Patent attributes
An improved driving circuit for piezoelectric lamps includes a power switch unit and at least one piezoelectric transformer. The power switch unit is connected to a power source. ON/OFF of the power switch unit controls power amount transmitted to the piezoelectric transformer. The piezoelectric transformer transforms the power and drives at least one load. Operation of the power switch unit is controlled by a duty cycle signal generated by a pulse modulation unit. The pulse modulation unit is connected to a buffer unit which generates a time series at start time to suppress instant output of the piezoelectric transformer, thereby to improve the problem of voltage surge at the start time happened to the conventional piezoelectric transformers.
