Head with active fly height control

US6577466B2 · kind B2 · utility

Assignee

• Seagate Technology LLC · US

Inventors

• Dallas W. Meyer · Prior Lake, US
• Mark J. Schaenzer · Eagan, US
• Zhu Feng · Pleasanton, US
• Chung Shih · Cupertino, US
• Chiu-Shing Frank Poon · Oakland, US
• Vidyadhara K. Gubbi · Milpitas, US

Key dates

• Filing date: Dec 21, 2001
• Grant date: Jun 10, 2003
• Expiry date: Dec 21, 2021

Classification

• Technology area (CPC G): Physics
• CPC primary: G11B2005/001
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

An apparatus and method for evaluating surface characteristics of a recording disc prior to incorporation into a disc drive. A glide test system includes a glide test head supportable over the disc, the glide test head having a negative-pressure air bearing slider and a contact sensor which outputs a signal when the glide test head contacts a feature of the disc surface. The glide test head and the disc are characterized as opposing plates of a variable capacitor with a dielectric layer therebetween including at least a layer of air supporting the glide test head. A voltage source, operably coupled to the glide test head and the disc, applies a fly height control voltage across the capacitor to adjust the fly height of the glide test head. The disc surface preferably comprises a data region configured to magnetically store data as the disc is rotated and a texturized landing zone configured to support the disc drive read/write head when the disc is stopped. The voltage source accordingly applies a first fly height control voltage to maintain the glide test head at a first glide distance over the data region and a second fly height control voltage to maintain the glide test head at …