US4841398A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Non linear magnetoresistive sensor
Assignee: Seagate Technology LLC
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Filing: 1987-02-17
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Granted: 1989-06-20
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Expires: 2007-02-17
Abstract
Abstract A non linear magnetoresistive sensor having a magnetoresistive strip with no transverse biasing (either permanent or current) such that the sensor is operated in its non linear mode. The sensor is useful in its non linear mode to determine the location of pulse peaks from encoded data from a medium by differentiating and determining the zero crossings of the detected signal.
Inventors
- 👤 Greg S. Mowry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:44
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; G11B5/398; G01; G01R; G01R33/00; G01R33/02; G01R33/06; G01R33/09; G01R33/096; G11B5/02; G11B5/09
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
204 words
Apparatus comprising: a magnetoresistive sensor mounted in a recording head adjacent a magnetic recording medium comprising: a sense region having a magnetization vector M aligned parallel to the easy axis in the absence of external magnetic fields from said recording medium; means for providing a sense current in the sense region having a vector J substantially parallel with said easy axis magnetization vector M; said magnetic recording medium mounted adjacent to said head such that relative motion between them can occur; the magnetic medium having a plurality of magnetization transitions recorded thereon providing magnetic flux pulses to the sense region as a transition passes the sensor, the peak flux amplitude of the pulse being sufficient to rotate the sense region magnetization vector M away from the sense current vector J so that the angle between them is in the range of 40 to 50 degrees, whereby the sensor operates in a non linear mode because of the initial alignment of sense current and magnetization vectors in absence of magnetic flux from the magnetic medium, and wherein the sensor's response in the region of the pulse peak from magnetic flux from the magnetic medium is approximately a linear function of magnetic flux of the transition.
Claim 2
Dependent Claim
204 words
Apparatus comprising: a magnetoresistive sensor mounted in a recording head adjacent a magnetic recording medium comprising: a sense region having a magnetization vector M aligned parallel to the easy axis in the absence of external magnetic fields from said recording medium; means for providing a sense current in the sense region having a vector J substantially parallel with said easy axis magnetization vector M; said magnetic recording medium mounted adjacent to said head such that relative motion between them can occur; the magnetic medium having a plurality of magnetization transitions recorded thereon providing magnetic flux pulses to the sense region as a transition passes the sensor, the peak flux amplitude of the pulse being sufficient to rotate the sense region magnetization vector M away from the sense current vector J so that the angle between them is in the range of 40 to 50 degrees, whereby the sensor operates in a non linear mode because of the initial alignment of sense current and magnetization vectors in absence of magnetic flux from the magnetic medium, and wherein the sensor's response in the region of the pulse peak from magnetic flux from the magnetic medium is approximately a linear function of magnetic flux of the transition.
References Cited (Backward Citations)
US3887944A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-06-19 | 1992-12-19 | 1993-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-19 | 1996-12-19 | 1997-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-19 | 2000-12-19 | 2001-06-20 | $7700.00 | Window Closed / Lapsed |