Patent · US Expired

Disk drive using a disturbance sensor for disturbance frequency-identification and suppression

US7345841B2 · kind B2 · utility

10Cited by
12References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 7, 2006
Grant dateMar 18, 2008
Priority date
Expiry dateFeb 7, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/59622
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic recording disk drive has a disturbance sensor and a disturbance frequency identifier that are used to adjust the frequency of a peak filter as the disturbance frequency changes. The sensor and the frequency identifier are separate from the servo control loop and thus do not rely on the head position error signal (PES) to predict the disturbance frequency. The adjustable peak filter is coupled in parallel with the servo feedback controller. The peak filter modifies the open loop transfer function and the error rejection function of the servo control loop to provide a higher rejection at the identified frequency. The peak filter may be switched out of or uncoupled from the servo feedback controller during track-seeking or as desired, depending on the amplitude of the sensor signal or the amplitude of the PES.

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