Patent ID: 7933090

Claim:
A disk drive comprising: a disk comprising a plurality of tracks; a head actuated over the disk; and control circuitry operable to: (a) set a maximum write current limit (MAX_Iw) and an maximum overshoot limit (MAX_OS); (b) initialize a write current to an initial write current (INIT_Iw) less than MAX_Iw, and initialize an overshoot to MAX_OS; (c) first sweep the write current from INIT_Iw to MAX_Iw, wherein for each write current: write data to a target track; and read the target track and measure a first quality metric; (d) measure a second quality metric associated with wide track erasure; (e) determine a quality of the write operations in response to the first and second quality metrics; (f) when the quality of the write operations does not exceed a threshold, decrease at least one of MAX_Iw and MAX_OS and re-execute steps (b)-(e); and (g) when the quality of the write operations exceeds the threshold, second sweep the write current from a minimum write current limit (MAX_Iw) to the adjusted MAX_Iw for a plurality of tracks to find an optimal write current for each track.