| 摘要 |
PROBLEM TO BE SOLVED: To generate a highly-accurate driving signal for a vibration apparatus that employs a piezoelectric element using an oscillated signal having a comparatively low frequency. SOLUTION: A piezoelectric element drive circuit 14 for outputting a signal that drives a piezoelectric element, the piezoelectric element drive circuit including: a frequency signal generation part 130 that outputs a frequency signal whose frequency is altered discretely; a voltage-controlled oscillator 34 that alters the frequency of an output signal based on an input voltage; a phase comparator 31 that compares the phase of the output signal from the frequency signal generation part and the phase of the output signal of the voltage-controlled oscillator; and loop filters 32 and 33 that input, into the voltage-controlled oscillator, an output voltage that is altered based on alterations in an output signal from the phase comparator. The output signal of the voltage-controlled oscillator is the signal that drives the piezoelectric element. COPYRIGHT: (C)2011,JPO&INPIT |
