Patent ID: 7315430
Filing Date: 2008-01-01
Classification: G11B

Abstract:
1. A magnetic disk drive comprising: a magnetic disk having a plurality of tracks in which a plurality of servo data areas and data recording areas between the servo data areas are formed; a spindle motor configured to hold and rotate the magnetic disk; a magnetic head for writing and reading data on said magnetic disk; a driving unit configured to move the magnetic head in a radial direction of said magnetic disk; and a servo controller configured to calculate the amount of positioning control of said magnetic head based on positional information and on repeatable runout compensation data received by said magnetic head from a flash memory and position said magnetic head at a target track on said magnetic disk; wherein, with regard to low frequency components of said positional information read by said magnetic head, which occur in the case that the center of rotation of said magnetic disk deviates more than one track, said servo controller controls the positioning of said magnetic head by calculating the amount of positioning control of said magnetic head to remove said low frequency components from said positional information and adding it to said amount of control calculated based on said positional information and said repeatable runout compensation data.