| 摘要 |
PROBLEM TO BE SOLVED: To provide a power supply device using a piezoelectric transformer that enables miniaturization, thereby solving such a problem of a conventional power supply device using a piezoelectric transformer that miniaturization is difficult because an element that establishes matching between a frequency applied to a primary side of the piezoelectric transformer and a resonance frequency of the piezoelectric transformer is required and two piezoelectric transformers need to be used.SOLUTION: Using a drive part for applying a voltage to a primary side of a piezoelectric transformer, a voltage that occurs on a secondary side of the piezoelectric transformer is fed back to the drive part through a capacitor. As a result, there occurs self-oscillation at a resonance frequency of the piezoelectric transformer, which eliminates a need for an oscillator and enables reduction of the number of piezoelectric transformers used to one. |
