Embodiments in accordance with the present invention provide a magnetic
disk drive with reduced noise during seek operation without causing any
delay in control response. According to one embodiment of the present
invention, a control circuit of a magnetic disk drive controls the drive
power supplied to a voice coil motor during a seek operation adapted to
move a magnetic head over a target track formed on a magnetic disk so as
to bring the travel speed of the magnetic head close to a predetermined
target speed. The control circuit determines a provisional current
according to the difference between the predetermined target speed and an
actual travel speed in an acceleration zone adapted to accelerate the
magnetic head to the predetermined target speed. If the provisional
current exceeds a limit specified in relation to an elapsed time from the
start of acceleration, the control circuit sets the limit as the current
of the drive power supplied to the voice coil motor to control the motor.