Patent ID: 6614612
Filing Date: 2003-09-02
Classification: G11B

Abstract:
A disk drive comprising:a motor for spinning a disk, the motor having input terminals for receiving control signals; a control loop for controlling the motor, the control loop comprising: an input terminal for receiving a reference control signal; an output terminal for providing a feedback signal from the motor, the feedback signal being indicative of operating characteristics of the motor; means for generating an error signal based upon the reference control signal and the feedback signal, the means having a plurality of input terminals, the input terminal of the velocity control loop being connected to a first input terminal of the means and the output terminal of the velocity control loop being connected to a second terminal of the means, the means further having an output terminal to carry the error signal; a filter being at least a second order filter connected to the output terminal of the means, the filter comprising: a filter section being one order below the filter, the filter section having an output terminal for supplying a first compensated signal; and an accumulator having an input terminal connected to the output terminal of the filter section and an output terminal electrically connected to an output terminal of the filter.