EP0063397A1
Expired / Lapsed
EP
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Magnetic sensor
Assignee: Koninklijke Philips NV
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Filing: 1982-04-09
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Granted: —
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Expires: 2002-04-09
Abstract
Abstract A magnetic sensor for sensing magnetic fields including two flat layers of electrically conductive ferromagnetic material (11, 16) each having an in-plane easy axis of magnetization (EA 1 , EA2) and each producing a resistance variation under the influence of a magnetic field Ha which originates from a source at an edge of the layer, which layers are situated a small distance apart parallel with respect to each other. In order to increase the sensor's sensitivity to small magnetic fields, in operation the layers (11, 16) convey current flowing in the same direction and are connected in parallel to the input terminals of a detection circuit (2, 9).
Inventors
- 👤 Johannes Adrianus C. Van Ooijen
- 👤 Jacobus Josephus Maria Ruigrok
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 13:43
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/02; G01R33/06; G01R33/09; G01R33/093; B; B82; B82Y; B82Y25/00; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; G11B5/3906; G11B5/3916; G11B5/3919; G11B5/3922; G11B5/3925; G11B5/3945; G11B5/3948; G11B5/3951; G11B5/3954
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
101 words
A magnetic sensor which uses the magneto-resistance effect of two magnetostatically coupled flat layers of electrically conductive ferromagnetic material having an easy axis of magnetization in the plane of the layer, which layers are situated a small distance apart parallel with respect to each other and give a response in the form of a resistance variation on application of a magnetic field having a component in the plane of the layers, characterized in that in operation the magneto-resistive layers convey currents flowing in the same direction and that they are connected in parallel to the input terminals of a detection circuit.
Claim 2
Dependent Claim
101 words
A magnetic sensor which uses the magneto-resistance effect of two magnetostatically coupled flat layers of electrically conductive ferromagnetic material having an easy axis of magnetization in the plane of the layer, which layers are situated a small distance apart parallel with respect to each other and give a response in the form of a resistance variation on application of a magnetic field having a component in the plane of the layers, characterized in that in operation the magneto-resistive layers convey currents flowing in the same direction and that they are connected in parallel to the input terminals of a detection circuit.
Claim 3
Dependent Claim
25 words
A sensor as claimed in Claim 1, characterized in that the magneto-resistive layers are separated from each other by a distance smaller than 30 nm.
Claim 4
Dependent Claim
29 words
A sensor as claimed in Claims 1 or 2, characterized in that the magneto-resistive layers are separated from each other by an intermediate layer of non-magnetic, electrically conductive material.
Claim 5
Dependent Claim
21 words
A sensor as claimed in Claim 3, characterized in that the thickness of the intermediate layer is smaller than 10 nm.
Claim 6
Dependent Claim
33 words
A sensor as claimed in Claim 1, 2, 3 or 4, characterized in that the layers have an elongate shape and that their easy axis of magnetization is parallel to their largest dimension.
Claim 7
Dependent Claim
36 words
A sensor as claimed in Claim 1, 2, 3, 4 or 5, characterized in that the directions of the magnetizations of the magneto-resistive layers in the quiescent state are transverse to the easy axes of magnetization.
Claim 8
Dependent Claim
35 words
A sensor as claimed in Claim 1, 2, 3, 4, 5 or 6, characterized in that the direction of the presented magnetic field is parallel to the easy axes of magnetization of the magneto-resistive layers.
Claim 9
Dependent Claim
40 words
A sensor as claimed in Claim 1, 2, 3, 4, 5, 6 or 7, characterized in that the direction of current pa s - sage through the magnetoresistive layers is transverse to the direction of the easy axes of magnetization.
References Cited (Backward Citations)
US3879760A
Cited
US3860965A
Cited
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