WO1991015012A3 - Shorted dual element magnetoresistive reproduce head exhibiting high density signal amplification - Google Patents

Shorted dual element magnetoresistive reproduce head exhibiting high density signal amplification Download PDF

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Publication number
WO1991015012A3
WO1991015012A3 PCT/US1991/001753 US9101753W WO9115012A3 WO 1991015012 A3 WO1991015012 A3 WO 1991015012A3 US 9101753 W US9101753 W US 9101753W WO 9115012 A3 WO9115012 A3 WO 9115012A3
Authority
WO
WIPO (PCT)
Prior art keywords
elements
dual element
shorted
shorting
signal
Prior art date
Application number
PCT/US1991/001753
Other languages
French (fr)
Other versions
WO1991015012A2 (en
Inventor
Neil Smith
Original Assignee
Eastman Kodak Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Eastman Kodak Co filed Critical Eastman Kodak Co
Priority to EP91907355A priority Critical patent/EP0484474B1/en
Priority to DE69119356T priority patent/DE69119356T2/en
Publication of WO1991015012A2 publication Critical patent/WO1991015012A2/en
Publication of WO1991015012A3 publication Critical patent/WO1991015012A3/en

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127—Structure or manufacture of heads, e.g. inductive
    • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
    • G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
    • G11B5/3903—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures
    • G11B5/3906—Details related to the use of magnetic thin film layers or to their effects
    • G11B5/3945—Heads comprising more than one sensitive element
    • G11B5/3948—Heads comprising more than one sensitive element the sensitive elements being active read-out elements
    • G11B5/3951—Heads comprising more than one sensitive element the sensitive elements being active read-out elements the active elements being arranged on several parallel planes
    • G11B5/3954—Heads comprising more than one sensitive element the sensitive elements being active read-out elements the active elements being arranged on several parallel planes the active elements transducing on a single track
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/02—Recording, reproducing, or erasing methods; Read, write or erase circuits therefor
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127—Structure or manufacture of heads, e.g. inductive
    • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
    • G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
    • G11B5/3903—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures
    • G11B5/399—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures with intrinsic biasing, e.g. provided by equipotential strips

Abstract

An MR dual element head (70) of the present invention solves a shorting problem between sensing and mutually biasing MR elements of a dual element head without suffering the penalty of signal reduction due to shunting of sense current. In a preferred embodiment, two MR elements (72, 74) are neither totally insulated from each other, nor shorted along their entire lengths by a contiguous conductive spacer, but are separated by an insulating layer (76) which has shorting stubs (78, 80) at its ends for electrically shorting the MR elements. A current (82) applied to the shorted MR elements splits into two currents (88, 90) that flow in the same direction through the substantially identical MR elements to provide the bias, and to serve as sense currents for detecting element resistance change. The MR elements are biased to operate in a magnetically unsaturated mode. This results in a 'bootstrapping' of short wavelength signals that effectively amplifies the reproduced signal over a broad region of the signal spectrum when the linear spacing between the MR elements is in the range of from one half to one times the linear distance between the flux changes recorded on the signal medium. In a second embodiment, MR elements (12, 14) are in contact with a conductive spacer (16) for their entire lengths.
PCT/US1991/001753 1990-03-29 1991-03-18 Shorted dual element magnetoresistive reproduce head exhibiting high density signal amplification WO1991015012A2 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP91907355A EP0484474B1 (en) 1990-03-29 1991-03-18 Shorted dual element magnetoresistive reproduce head exhibiting high density signal amplification
DE69119356T DE69119356T2 (en) 1990-03-29 1991-03-18 HIGH DENSITY AMPLIFICATION POINTING MAGNETORESISTIVE PLAYBACK HEAD WITH SHORT-CLOSED DOUBLE ELEMENT

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US07/500,978 US5084794A (en) 1990-03-29 1990-03-29 Shorted dual element magnetoresistive reproduce head exhibiting high density signal amplification
US500,978 1990-03-29

Publications (2)

Publication Number Publication Date
WO1991015012A2 WO1991015012A2 (en) 1991-10-03
WO1991015012A3 true WO1991015012A3 (en) 1991-11-28

Family

ID=23991654

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1991/001753 WO1991015012A2 (en) 1990-03-29 1991-03-18 Shorted dual element magnetoresistive reproduce head exhibiting high density signal amplification

Country Status (5)

Country Link
US (3) US5084794A (en)
EP (1) EP0484474B1 (en)
JP (1) JP3021042B2 (en)
DE (1) DE69119356T2 (en)
WO (1) WO1991015012A2 (en)

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MY107733A (en) * 1991-05-21 1996-05-30 Onstream Inc Combined read/write magnetic head
US5266786A (en) * 1991-10-01 1993-11-30 Ncr Corporation Magnetoresistive head for reading magnetic ink characters
US5378885A (en) * 1991-10-29 1995-01-03 Mars Incorporated Unshielded magnetoresistive head with multiple pairs of sensing elements
US5270892A (en) * 1992-06-05 1993-12-14 Hewlett-Packard Company Conductor configuration for magnetoresistive transducers
US5309304A (en) * 1992-06-05 1994-05-03 Hewlett-Packard Company Magnetoresistive transducer conductor configuration
US5323285A (en) * 1992-06-23 1994-06-21 Eastman Kodak Company Shielded dual element magnetoresistive reproduce head exhibiting high density signal amplification
US5945007A (en) * 1992-10-20 1999-08-31 Cohen; Uri Method for etching gap-vias in a magnetic thin film head and product
US5621595A (en) * 1992-10-20 1997-04-15 Cohen; Uri Pinched-gap magnetic recording thin film head
US5309305A (en) * 1992-11-16 1994-05-03 Read-Rite Corporation Dual element magnetoresistive sensing head
US5485333A (en) * 1993-04-23 1996-01-16 Eastman Kodak Company Shorted DMR reproduce head
US5406433A (en) * 1993-12-01 1995-04-11 Eastman Kodak Company Dual magnetoresistive head for reproducing very narrow track width short wavelength data
EP0663661B1 (en) * 1994-01-12 1999-06-23 Eastman Kodak Company Magnetically capped dual magnetoresistive reproduce head and method of making same
EP0676746B1 (en) * 1994-03-09 1999-08-04 Eastman Kodak Company Spin-valve dual magnetoresistive reproduce head
JP2970455B2 (en) * 1994-03-14 1999-11-02 株式会社デンソー Method of manufacturing magnetoresistive element and magnetic field processing apparatus therefor
US5696654A (en) * 1994-04-21 1997-12-09 International Business Machines Corporation Dual element magnetoresistive sensor with antiparallel magnetization directions for magnetic state stability
US5442508A (en) * 1994-05-25 1995-08-15 Eastman Kodak Company Giant magnetoresistive reproduce head having dual magnetoresistive sensor
US6510031B1 (en) 1995-03-31 2003-01-21 International Business Machines Corporation Magnetoresistive sensor with magnetostatic coupling to obtain opposite alignment of magnetic regions
US5914630A (en) * 1996-05-10 1999-06-22 Vtc Inc. MR head preamplifier with output signal amplitude which is independent of head resistance
JPH11510911A (en) * 1996-06-12 1999-09-21 フィリップス エレクトロニクス ネムローゼ フェンノートシャップ Magnetoresistive magnetic field sensor
JPH1098220A (en) * 1996-09-20 1998-04-14 Sanyo Electric Co Ltd Magnetoresistance effect device
US5684658A (en) * 1996-10-07 1997-11-04 Headway Technologies, Inc. High track density dual stripe magnetoresistive (DSMR) head
US5721008A (en) * 1996-10-15 1998-02-24 Seagate Technology, Inc. Method for controlling sensor-to-sensor alignment and material properties in a dual magnetoresistive sensor
US5766780A (en) * 1996-10-15 1998-06-16 Seagate Technology, Inc. Reversed order NIMN exchange biasing for dual magnetoresistive heads
US5706151A (en) * 1996-12-12 1998-01-06 Eastman Kodak Company Low bias current paired magnetoresistive head with misaligned anisotropy axes
US6118622A (en) 1997-05-13 2000-09-12 International Business Machines Corporation Technique for robust resetting of spin valve head
US5748399A (en) * 1997-05-13 1998-05-05 International Business Machines Corporation Resettable symmetric spin valve
US5825595A (en) * 1997-05-13 1998-10-20 International Business Machines Corporation Spin valve sensor with two spun values separated by an insulated current conductor
WO1999059145A1 (en) * 1998-05-13 1999-11-18 Storage Technology Corporation Method for reading both high and low density signals with an mr head
US6128149A (en) * 1998-10-23 2000-10-03 International Business Machines Corporation Method and system for detecting common mode disturbances from a dual stripe magnetoresistive head
US6185079B1 (en) 1998-11-09 2001-02-06 International Business Machines Corporation Disk drive with thermal asperity reduction circuitry using a magnetic tunnel junction sensor
JP2001273611A (en) 2000-03-28 2001-10-05 Alps Electric Co Ltd Thin film magnetic head
JP2002074614A (en) * 2000-08-25 2002-03-15 Alps Electric Co Ltd Magnetic head
US6894878B1 (en) 2002-07-10 2005-05-17 Maxtor Corporation Differential GMR head using anti-parallel pinned layers
US7227726B1 (en) 2002-11-12 2007-06-05 Storage Technology Corporation Method and system for providing a dual-stripe magnetoresistive element having periodic structure stabilization
US7167193B2 (en) * 2003-02-28 2007-01-23 Eastman Kodak Company Active cooling system for laser imager
US7573684B2 (en) * 2005-04-13 2009-08-11 Seagate Technology Llc Current-in-plane differential magnetic tri-layer sensor

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US4343026A (en) * 1980-07-09 1982-08-03 Spin Physics, Inc. Magnetoresistive head employing field feedback
EP0063397A1 (en) * 1981-04-22 1982-10-27 Koninklijke Philips Electronics N.V. Magnetic sensor
EP0101825A1 (en) * 1982-08-30 1984-03-07 International Business Machines Corporation Magnetoresistive sensor for vertically recorded data and method of sensing such data

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EP0063397A1 (en) * 1981-04-22 1982-10-27 Koninklijke Philips Electronics N.V. Magnetic sensor
EP0101825A1 (en) * 1982-08-30 1984-03-07 International Business Machines Corporation Magnetoresistive sensor for vertically recorded data and method of sensing such data

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Also Published As

Publication number Publication date
US5193038A (en) 1993-03-09
US5357388A (en) 1994-10-18
JP3021042B2 (en) 2000-03-15
JPH04507163A (en) 1992-12-10
DE69119356D1 (en) 1996-06-13
EP0484474A1 (en) 1992-05-13
DE69119356T2 (en) 1996-12-19
EP0484474B1 (en) 1996-05-08
US5084794A (en) 1992-01-28
WO1991015012A2 (en) 1991-10-03

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