Motor driver

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.