Patent ID: 6975474
Filing Date: 2005-12-13
Classification: G11B

Abstract:
1. A disk drive comprising: a head having a giant magnetoresistive (GMR) read element which reads data from a disk medium and a write element which writes data to the disk medium; an actuator mechanism on which the head is mounted and which moves to a specified position on the disk medium; current supply units which supply a bias current and a write current to the GMR read element and the write element, respectively; and a control unit which determines, on the basis of a resistance value of the GMR read element, an optimum bias and write currents required to successfully execute pinning reset on the GMR read element and which allows the optimum bias and write currents to be supplied to the head, wherein, when a read error occurs during a read operation of reading data from the disk medium, the control unit causes the actuator mechanism to move the head to a specified position on the disk medium or outside the range of the disk medium and then causes the current supply units to supply the optimum bias and write currents to the head, and wherein, if recovery from the read error fails, the control unit changes the bias current value to re-perform the read operation.