Patent ID: 11948604
Assignee: TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 7:
8. A magnetic disk device comprising:
a magnetic disk;
a magnetic head that accesses the magnetic disk;
a motor that moves the magnetic head;
a ramp;
a motor driver that starts a retract operation of retracting the magnetic head to the ramp by controlling a voltage applied to the motor when a voltage value of a power supply voltage falls below a first threshold; and
a processor that transmits, to the motor driver, an instruction related to applying a brake to movement of the magnetic head when the voltage value of the power supply voltage falls below a second threshold larger than the first threshold, wherein
the motor driver applies a voltage of a pulsed waveform to the motor a plurality of times in the retract operation, and controls a wave height of a voltage of a pulsed waveform to be applied first among the voltages of the pulsed waveforms applied the plurality of times according to the instruction.