| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain an excellently controllable and stable high output using a piezoelectric transformer. <P>SOLUTION: A piezoelectric transformer actuating circuit 74 is operated by a driving pulse S72 output from a controller 72, and a piezoelectric transformer 75 is actuated by the piezoelectric transformer actuating circuit 74 to output a high AC voltage from the transformer 75. The high AC voltage is converted to a high DC voltage through a rectifier 76. The high DC voltage is compared with a target voltage V53a output from a digital/analog converter DAC 53a by an output voltage comparator 78, and a comparative result S78 is controlled to constitute a rectangular wave by the controller 72. Consequently, control for a stable and constant high output is performed from a low frequency band to a high frequency band close to the resonant frequency of the piezoelectric transformer 75. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
