US 2015/0091476 A1 · DEVICE FOR DRIVING PIEZO-ACTUATOR AND DRIVING METHOD THEREFOR

Abstract

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.

Claims17

Dependent claims

A device for driving a piezoelectric actuator, comprising:

a signal generation unit for generating a signal having a certain frequency;
and
a modulation unit for modulating and outputting the signal generated by the signal generation unit,
wherein the modulation unit comprises a density modulation unit for executing a first mode in which an operation of outputting as many input signals as a first predetermined number and an operation of blocking as many input signals as a second predetermined number are repeated, or a second mode in which an operation of outputting input signals for a first interval and an operation of blocking the input signals for a second interval are repeated.

1 more element

Dependencies are inferred from the claim text.

Device for driving piezo-actuator and driving method therefor

Life of this patent

Device for driving piezo-actuator and driving method therefor

Life of this patent

Abstract

Claims17