Apparatus and method for resetting a Z-axis sensor flux guide
AssigneeEverspin Technologies, Inc.
InventorsLianjun Liu, Phillip Mather
Life of this patent
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Abstract
A method and apparatus eliminate magnetic domain walls in a flux guide by applying, either simultaneously or sequentially, a current pulse along serially positioned reset lines to create a magnetic field along the flux guide, thereby removing the magnetic domain walls. By applying the current pulses in parallel and stepping through pairs of shorter reset lines segments via switches, less voltage is required.
Claims27
A method of resetting flux guides in a field sensor, comprising:
- applying a first field to a first portion of a flux guide to re-orient magnetic domains of the first portion of the flux guide to a predetermined orientation;
- applying a second field to a second portion of the flux guide to re-orient magnetic domains of the second portion of the flux guide to the predetermined orientation;
- applying a third field to a third portion of the flux guide to re-orient magnetic domains of the third portion of the flux guide to the predetermined orientation;
- and
- applying a fourth field to a fourth portion of the flux guide to re-orient magnetic domains of the third portion of the flux guide to the predetermined orientation.
A method of resetting a flux guide in a field sensor, the flux guide including n adjacent portions, wherein each portion has one of a plurality of n reset lines positioned adjacent thereto, where n is an integer greater than 1, the method comprising:
- applying one of n current pulses to each of the n reset lines and, in response thereto, generating a magnetic field in the n reset lines which re-orient magnetic domains of the flux guide to a predetermined orientation.
A field sensor including a plurality of magnetic field sensors, each sensor, comprising:
- a sense element defining a plane;
- a flux guide configured to direct a magnetic field perpendicular to the plane into the plane, the flux guide including n adjacent portions of a continuous line, where n is an integer greater than 1;
- a plurality of n reset lines, each reset line positioned uniquely adjacent one of the n portions;
- and
- circuitry coupled to the reset lines and configured to:
- apply a plurality of current pulses, one each to each of the n reset lines, thereby creating a field in each of the portions to re-orient magnetic domains therein to a predetermined orientation.
Dependencies are inferred from the claim text.