Patent ID: 6650084
Filing Date: 2003-11-18
Classification: H02P

Abstract:
A motor driver for driving a three-phase motor having coils, said motor driver comprising:a synchronized signal generating means for generating synchronized signals with the rotation of said motor by comparing each of induction voltages generated in said coils with a specified standard voltage; a sloped wave signal generating means for generating from said synchronized signals a sloped wave signal with a waveform including sloped portions, the frequency of said sloped wave signal increasing as said motor rotates faster; a noise mask signal generating means for varying a standard value according to a change in the amplitude of said sloped wave signal and generating a noise mask signal by comparing said standard value with said sloped wave signal; a noise mask means for removing noise from said synchronized signals by using said noise mask signal; and a current supplying means for supplying currents to said coils of said motor by using said synchronized signals from which noise has been removed by said noise mask means.