Patent · US Active

Closed-loop fly height control using transfer function between harmonic response and heater input

US10204650B1 · kind B1 · utility

1Cited by
11References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 13, 2018
Grant dateFeb 12, 2019
Priority date
Expiry dateAug 13, 2038

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2005/0021
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Gain values used by a variable gain amplifier (VGA) to read servo marks of a heat-assisted recording medium are measured. Sector-specific, repeatable gain values that indicate an expected VGA gain at a desired clearance are determined based on the measured gain values. The sector-specific, repeatable gain values are used as input to a closed-loop clearance controller together with measured values of servo VGA gain while writing data to the recording medium.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.