Patent ID: 6404570
Filing Date: 2002-06-11
Classification: G11B

Abstract:
In a disk drive including a recording head for reading/writing information to/from a rotating magnetic disk having a plurality of concentric tracks, a method of adaptive channel optimization comprising the steps of:(a) seeking to a selected track of said disk; (b) setting an initial write current, Iw=I1; (c) preconditioning said selected track by writing a first pattern to opposite sides of said selected track a predetermined distance off-track; (d) writing a second data pattern centered on said selected track; (e) setting an initial boost level, B=B1; (f) setting an initial bandwidth, BW=BW1; (g) setting an optimum threshold that is approximately half-way between upper and lower thresholds that produce a first error rate; (h) determining an off-track margin as a function of how far off-track said head may be positioned while meeting a second error rate; (i) repeating steps (g) and (h) for bandwidths BW2 through BWn, where n is an integer greater than one; (i) repeating steps (f)-(i) for boost levels B2 through Bm, where m is an integer greater than one; (k) determining the greatest off-track margin value resulting from steps (g)-(j) and setting Iw, B, and BW accordingly; (l) repeating step (g) using the settings of Iw, B, and BW of step (k); and (m) determining on-track values of threshold margin and timing margin at said second error rate and a third error rate, respectively.