Patent ID: 6801382
Filing Date: 2004-10-05
Classification: G11B,H02P

Abstract:
A magnetic disk storage apparatus comprising: a first motor for rotating magnetic disk; a magnetic head for reading information from recording tracks on the magnetic disk; and a first motor driving control circuit for controlling drive currents of the first motor,wherein the first motor is a multi-phase brushless motor in which the potential of a center tap of the multi-phase brushless motor is made to be floating, and wherein a driving control circuit of the first motor performs driving by feedback control so that a coil of one of the phases is driven with an amplitude at which an applied voltage becomes equal to a source voltage, a coil of a second phase is driven with gradually changing voltages so that a current of sine waveform is delivered; and a coil of a third phase is controlled so that a total current flowing through all coils becomes a predetermined current value.