Patent ID: 6351089
Filing Date: 2002-02-26
Classification: H02P

Abstract:
A control system for a linear vibration motor, said linear vibration motor comprising:a stator provided with one of a permanent magnet and a winding; a vibrator provided with the other of said permanent magnet and said winding, and said winding being fed with a drive current to generate a magnetic field which interacts with said permanent magnet to cause said vibrator to reciprocate linearly relative to said stator for producing a vibration; said control system including: a controller which detects an ongoing amplitude of said vibrator and provides ON-periods of feeding said driving current to said winding in a varying amount based upon the ongoing amplitude detected in order to keep a vibration amplitude of said vibrator constant; wherein said controller provides OFF-periods in which said controller instructs not to feed said driving current and in which said controller detects a voltage developed across said winding and determines said the ongoing amplitude based upon said voltage.