Patent ID: 6501242
Filing Date: 2002-12-31
Classification: G11B

Abstract:
A rotating magnetic disk drive data storage device, comprising:a disk drive base; a rotatably mounted disk and spindle assembly, said disk and spindle assembly comprising at least one rigid disk for recording magnetically encoded data on at least one surface of said at least one rigid disk, said at least one disk being permanently mounted on said disk and spindle assembly; a movable actuator supporting at least one transducer head, said actuator positioning said at least one transducer head to access said magnetically encoded data on said at least one surface of said at least one rotatably mounted disk; a spindle motor rotating said at least one rotatably mounted disk and spindle assembly, said spindle motor having a multi-phase electro-magnetic stator and a permanent magnet rotor; a spindle motor driving apparatus, said spindle motor driving apparatus providing drive current to said multi-phase electromagnetic stator, said spindle motor driving apparatus sequentially switching phases of said drive current at corresponding angles of rotation of said disk and spindle assembly, said spindle motor driving apparatus varying by a respective semi-random offset each successive angle of rotation at which said spindle motor driving apparatus switches phase of said drive current.