| 摘要 |
<P>PROBLEM TO BE SOLVED: To attain stable drive by performing locking to a resonance frequency of a piezoelectric element with a simple configuration. <P>SOLUTION: A sample hold device 4 and a comparator 5 connected to a detection winding 25 as one winding of a transformer 2 for driving the piezoelectric element 1 detect if an actual driving frequency shifts to a higher side or a lower side than a resonance frequency of the piezoelectric element and increase or decrease a dividing ratio of a reference clock to adjust the driving frequency of the piezoelectric element 1 and lock it to the resonance frequency, thus attaining stable piezoelectric element drive. <P>COPYRIGHT: (C)2007,JPO&INPIT |
