Write precompensation for head misalignment
AssigneeSeagate Technology LLC
InventorHarry S. Edelman
Life of this patent
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Abstract
Misalignment of a transducer head over a bit-patterned media (BPM) may cause a bit to experience conflicting magnetization forces from the writer, resulting in improperly written data and stored data corruption. The likelihood of data corruption is reduced when a write transition is performed when the write sync margin is increased or maximized. Therefore, a write precompensation system may calculate time shift information for adjusting the timing of an individual write current transition at the transducer that compensates for write sync margin degradation due to any or all of skew angle of the transducer, track misregistration, and write field curvature.
Claims20
A method comprising:
- calculating a distance between a first point on a target magnetic field line and a second point on a shifted magnetic field line, the shifted magnetic field line being offset from the target magnetic field line due to a skew angle of a transducer;
- and
- determining an adjustment to write signal timing to increase a write sync margin based on the calculated distance.
A system comprising:
- a write precompensator that adjusts write signal timing to increase a write sync margin based on a distance between a first point on a target magnetic field line and a second point on a shifted magnetic field line, the shifted magnetic field line being offset from the target magnetic field line due to a combination of skew angle and track misregistration of the transducer.
One or more non-transitory computer-readable storage media encoding computer-executable instructions for executing on a computer system a computer process, the computer process comprising:
- calculating a distance between a first point on a target magnetic field line and a second point on a shifted magnetic field line, the shifted magnetic field line being offset from the target magnetic field line due to a skew angle of a transducer;
- and
- determining a write signal timing adjustment to increase a write sync margin based on the calculated distance.
Dependencies are inferred from the claim text.