Patent ID: 6961201
Filing Date: 2005-11-01
Classification: G11B

Abstract:
1. A magnetic disk apparatus comprising a disk for recording data, a motor for rotating said disk, speed detection means for detecting a speed of said motor and generating a detected speed signal, target speed generation means for generating a target speed signal of said motor, motor control means for generating a control signal of said motor on the basis of the target speed signal and the detected speed signal, a head for recording/reproducing data on/from said disk, and an actuator for moving said head, wherein: said apparatus has a low-rotation mode for decreasing the revolution number of said disk when data is neither recorded nor reproduced, in said low-rotation mode, any control signal for decelerating said disk is not generated by said motor control means to permit the disk to be decelerated by inertia, and said disk is accelerated when the detected speed falls below a target speed, and said head floats above said disk when recording/reproducing data, and during said low-rotation mode, said head moves to a periphery part of said disk, and said target speed is set at a revolution number that corresponds to a float amount of said head larger than the float amount during recording/reproducing data.