Patent Number: 6,166,876

Title: Minimizing settling time in a disc drive servo system

Abstract: An apparatus and method are disclosed for minimizing settling time in a disc drive servo system. The disc drive includes a head adjacent a rotatable disc on which a plurality of tracks are defined and a motor which controllably positions the head in response to current applied to the motor. A servo circuit is provided to settle the head onto a destination track at the conclusion of a seek operation by determining velocity of the head at a selected distance from the destination track, comparing the velocity to a desired velocity of the head at the selected distance from the destination track, adding a settling gain to a current command signal to generate a modified current command signal in relation to a difference between the velocity and the desired velocity, and using the modified current command signal to settle the head onto the destination track. The addition of the settling gain serves to add an additional zero to the response of the servo circuit, with the placement of the zero preferably determined in relation to a weighting of the locations of the closest two poles of the response.

Inventors: Liu; Zhiqiang (Oklahoma City, OK)

Assignee: Seagate Technology, Inc.

International Classification: G11B 21/08 (20060101); G11B 5/55 (20060101); G11B 005/55 ()

Expiration Date: 12/26/2017