MR preamplifier having feedback loops for minimizing differential low frequency components and regulating common mode low frequency components of the preamplifier output signal
US5327303A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 18, 1992 |
| Grant date | Jul 5, 1994 |
| Priority date | — |
| Expiry date | Dec 18, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0016
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A preamplifier circuit amplifies signals from a magneto-resistive element. The preamplifier circuit utilizes a voltage regulator to regulate one terminal of a magneto-resistive element at a predetermined voltage. A first feedback loop is used to minimize a differential DC component and a differential low frequency component of the differential output signal. A second feedback loop is utilized to cause a common mode component of the differential output signal to track an externally supplied reference voltage. The preamplifier of the present invention protects the magneto-resistive elements from short circuits of the disc medium, is powered by a single-ended power supply, and is capable of being coupled with other circuitry without physical coupling capacitors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.