Patent ID: 6909575
Filing Date: 2005-06-21
Classification: G11B

Abstract:
1. A magnetic disk drive, comprising: a voice coil motor (VCM) for performing a seek operation that positions a magnetic head in a predetermined track; a VCM current detection amplifier (AMP) for measuring the VCM current supplied to said VCM; a VCM voltage detection amplifier (AMP) for measuring the VCM voltage applied to both ends of said VCM a channel for sampling position information of said magnetic head at said seek operation; and a CPU for calculating VCM back electromotive force (BEMF) based on a measurement result by said VCM current detection AMP and said VCM voltage detection AMP, detecting the traveling velocity of said magnetic disk from the difference of the position information of a sample result by said channel, estimating the coil temperature of said VCM from the difference between the traveling velocity detected and the BEMF calculated by said calculation, and moving said VCM at said seek operation when said estimated coil temperature exceeds a specified value.