| 摘要 |
<p>A device for driving a piezo-actuator comprises: a signal generating unit for generating signals having a constant frequency; and a modulation unit for modulating the signals generated from the signal generating unit and outputting the modulated signals, wherein the modulation unit comprises a density modulation unit which performs a first mode for repeating an operation for outputting an input signal at a first constant number and an operation for blocking the input signal at a second constant number, and which performs a second mode for repeating an operation for outputting the input signal during a first period and an operation for blocking the input signal during a second period. The device for driving the piezo-actuator and the method therefor can reduce the noise generated when the piezo-actuator for an automatic focus function of a camera is driven.</p> |
