Patent ID: 9645471
Date: 2017-05-09
CPC Classifications: G02B,G03B

Claim:
1. A driving circuit of a voice coil motor having a mover, comprising: a converting unit including a table storing a trigonometric function waveform of a trigonometric function having a specific period and configured to convert a position command value into an internal command value varied based on a waveform having a period which is half of the specific period of the trigonometric function by reading the trigonometric function waveform from the table when the position command value is changed, the position command value being indicative of a position of the mover and changeable step by step; and a driving unit configured to receive a position detection value indicating a current position of the mover from a sensor and drive the voice coil motor such that the position detection value matches the internal command value, wherein a transition frequency, which is a reciprocal of the specific period of the trigonometric function, is set to fall within a loop bandwidth by a loop gain compensation of the driving unit and is offset from a resonant frequency of the voice coil motor, and wherein the loop bandwidth of the driving unit is set according to the voice coil motor.