Patent ID: 8476889
Filing Date: 2013-07-02
Classification: B41J,G03G,H01L,H02M

Abstract:
1. A piezoelectric transformer driving device, comprising: a piezoelectric transformer with a certain resonance frequency configured such that when an input voltage is intermittently applied to a primary side, an alternating high voltage is output from a secondary side; a switching part configured to generate the input voltage by switching based on a control signal having a control frequency, and configured to supply the voltage to the piezoelectric transformer; a switching control part configured to control the control frequency of the control signal based on a comparison result, and configured to supply the control signal to the switching part; a reference voltage waveform generation part configured to switch between a first voltage value as a target value, a second voltage value that is lower than the first voltage value, and a third voltage value that is higher than the first voltage value, within a given unit time so that a reference voltage waveform is generated; a monitor voltage generation part configured to generate a monitor voltage waveform based on the high voltage output from the piezoelectric transformer; and a comparison part configured to compare the reference voltage waveform with the monitor voltage waveform to generate the comparison result, and configured to supply the comparison result to the switching control part, wherein the reference voltage waveform is a single continuous waveform that varies between the first voltage value, the second voltage value and the third voltage value.