公开(公告)号：DE3750315T2

公开(公告)日：1995-03-09

申请号：DE3750315

申请日：1987-05-19

Applicant: IBM

Inventor： CHRISTENSEN THOMAS CHARLES ,  JAWORSKI RICHARD CASIMIR ,  COKER JONATHAN DARREL ,  KERWIN GREGORY JOHN ,  CUNNINGHAM EARL ALBERT ,  PALMER DEAN CURTIS ,  ROEPKE JEFFREY RALPH

IPC: G11B5/09 ,  G11B5/00 ,  G11B5/012 ,  G11B5/035 ,  G11B5/455 ,  G11B20/18 ,  G11B27/36

Abstract: A magnetic disk drive channel circuitry is shown and described that generates eight incremental values of write current and eight incremental values of delta-V (the minimum voltage change per unit time which tests signals to discriminate between data and noise). Each of these variable parameter values may be program selected by a three bit bus signal. This variability testing of and adaptation to the optimum parameter value for each head media combination and by grouping tracks in contiguous data bands, the parameters may be optimized for tracks near the inner diameter, the outer diameter and in the middle band. The variable delta-V can also be used as an additional data recovery tool wherein re-reading with a lower value enhances recovery of missing bit errors and re-reading with an increased value can assist recovery from an extra bit error.

公开(公告)号：DE3750315D1

公开(公告)日：1994-09-08

申请号：DE3750315

申请日：1987-05-19

Applicant: IBM

Inventor： CHRISTENSEN THOMAS CHARLES ,  JAWORSKI RICHARD CASIMIR ,  COKER JONATHAN DARREL ,  KERWIN GREGORY JOHN ,  CUNNINGHAM EARL ALBERT ,  PALMER DEAN CURTIS ,  ROEPKE JEFFREY RALPH

IPC: G11B5/09 ,  G11B5/00 ,  G11B5/012 ,  G11B5/035 ,  G11B5/455 ,  G11B20/18 ,  G11B27/36

Abstract: A magnetic disk drive channel circuitry is shown and described that generates eight incremental values of write current and eight incremental values of delta-V (the minimum voltage change per unit time which tests signals to discriminate between data and noise). Each of these variable parameter values may be program selected by a three bit bus signal. This variability testing of and adaptation to the optimum parameter value for each head media combination and by grouping tracks in contiguous data bands, the parameters may be optimized for tracks near the inner diameter, the outer diameter and in the middle band. The variable delta-V can also be used as an additional data recovery tool wherein re-reading with a lower value enhances recovery of missing bit errors and re-reading with an increased value can assist recovery from an extra bit error.