Patent · US Expired

Preamplifier bias circuit for use in an AC coupled magnetoresistive read head amplifier

US6005733A · kind A · utility

12Cited by
15References
39Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 12, 1997
Grant dateDec 21, 1999
Priority date
Expiry dateJun 12, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2005/0018
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A preamplifier bias circuit for use in an AC coupled magnetoresistive read head amplifier which includes a pair of head contacts, a pair of amplifier inputs, a pair of coupling capacitors and a means for selectively shunting the amplifier inputs and rapidly charge the coupling capacitors. The pair of head contacts and the pair of amplifier inputs couple the preamplifier bias circuit to a magnetoresistive element and a read amplifier, respectively. Each of the coupling capacitors is connected between one of the head contacts and one of the amplifier inputs to block a static potential across the magnetoresistive element. The means for selectively shunting the amplifier inputs selectively provides a low impedance path to rapidly charge the coupling capacitors and clamps the amplifier inputs to a known potential. By selectively providing a low impedance path, the AC coupled magnetoresistive read head amplifier can be protected and its associated delay time prior to operation can be decreased.

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