Patent ID: 6747834
Filing Date: 2004-06-08
Classification: G11B

Abstract:
A disk drive comprising:a head arm having a head; a motor for rotating said head arm on an axis thereof to move said head in a direction across a track on a disk; a tracking position detection device for detecting a tracking position of said head by detecting a position of said head arm portion moving with said head; and a motor drive portion for driving said motor based on information from said tracking position detection device, wherein said tracking position detection device comprises, a detector for outputting two position detection signals having a predetermined phase difference as said head moves; and a signal processor for performing signal processing on said two position detection signals and for providing information used in controlling the motor wherein said detector outputs two position detection signals having a phase difference of 180 degrees along with movement of said head; and said signal processor obtains a reference voltage level by averaging said two position detection signals.