Patent ID: 7973520
Filing Date: 2011-07-05
Classification: H01L,H02M

Abstract:
1. A piezoelectric transformer type high-voltage power source apparatus to control an output voltage from a piezoelectric transformer to a load, the apparatus comprising: an output voltage detection unit to compare the output voltage of the piezoelectric transformer with an output control voltage, and to output a digital value according to the comparison; and a driving control unit to control a driving frequency and a duty rate of the piezoelectric transformer according to the digital value, wherein the driving control unit comprises: a driving frequency control unit to control the driving frequency according to the digital value; an off time setting unit to set an OFF time that stops a driving voltage from being applied to the piezoelectric transformer; a driving voltage generation unit to generate the driving voltage; and a selection unit to select an output value from the driving frequency control unit or an output value from the off time setting unit according to an output value of the driving voltage generation unit, and to output the selected output value to the driving voltage generation unit, wherein the driving voltage generation unit generates the driving voltage based on the driving frequency controlled by the driving frequency control unit, the OFF time set by the off time setting unit, and the output value from the selection unit.