Abstract:
A magnetic field sensor includes at least one coil responsive to an AC coil drive signal; at least one magnetic field sensing element responsive to a sensing element drive signal and configured to detect a directly coupled magnetic field generated by the at least one coil and to generate a magnetic field signal in response to the directly coupled magnetic field; a processor responsive to the magnetic field signal to compute a sensitivity value associated with detection of the directly coupled magnetic field and substantially independent of a reflected magnetic field reflected by a conductive target disposed proximate to the at least one magnetic field sensing element; and an output signal generator configured to generate an output signal of the magnetic field sensor indicative of the reflected magnetic field.
Abstract:
Systems and methods described herein are directed towards integrating a shield layer into a current sensor to shield a magnetic field sensing element and associated circuitry in the current sensor from electrical, voltage, or electrical transient noise. In an embodiment, a shield layer may be disposed along at least one surface of a die supporting a magnetic field sensing element. The shield layer may be disposed in various arrangements to shunt noise caused by a parasitic coupling between the magnetic field sensing element and the current carrying conductor away from the magnetic field sensing element.
Abstract:
A pressure sensor comprises a deformable substrate, at least one coil supported by the substrate and responsive to a changing coil drive signal to produce a changing magnetic field, a fluid chamber having a first wall formed by the substrate and a second wall formed by a conductive material and positioned proximate to the at least one coil so that the changing magnetic field produces eddy currents within the conductive material that generate a reflected magnetic field, and at least one magnetic field sensing element configured to detect the reflected magnetic field and produce a signal responsive to a distance between the magnetic field sensing element and the second wall. The substrate is deformable by fluid pressure within the fluid chamber and the deformation of the substrate changes the distance between the magnetic field sensing element and the second wall.
Abstract:
A pressure sensor includes a conductive substrate having a cavity which forms a thin portion that can be deformed by a pressure differential. A magnetic field sensor has at least one coil responsive to a changing coil drive signal and positioned proximate to the thin portion of the substrate that induces eddy currents in the thin portion that generate a reflected magnetic field. Magnetic field sensing elements detect the reflected magnetic field and generate a magnetic field signal. The magnetic field sensor is positioned so that deformation of the thin portion of the substrate causes a distance between the thin portion of the substrate and the magnetic field sensor to change.
Abstract:
A magnetic field sensor can include a substrate disposed in an x-y plane with x and y axes; one or more magnetoresistance elements, wherein magnetic directions of reference layers of each of the one or more magnetoresistance elements are parallel to the x axis; wherein the one or more magnetoresistance elements are operable to generate a magnetoresistance element signal; a first current conductor operable to generate a first AC magnetic field in an x-direction and a second current conductor operable to generate a second AC magnetic field in a y-direction; and a component determination circuit comprising at least two of: a first demodulator to demodulate the magnetoresistance element signal with a first clock signal with a first frequency, a second demodulator coupled to demodulate the magnetoresistance element signal with the first clock signal or with a second clock signal with a second frequency, or a low pass filter operable to filter the magnetoresistance element signal.
Abstract:
A magnetic field sensor can include a substrate, a first magnetoresistance element disposed over the substrate and including a first maximum response axis and a first bias layer structure configured to generate a first bias magnetic field with a first magnetic direction between ninety degrees and sixty degrees relative to the first maximum response axis. The magnetic field sensor can also include a second magnetoresistance element disposed over the substrate and including a second maximum response axis parallel to the first maximum response axis and a second bias layer structure configured to generate a second bias magnetic field with a second magnetic direction parallel to the first magnetic direction and opposed to the first magnetic direction. The first and second magnetoresistance elements can each have a pair of electrical contacts for coupling to circuits.
Abstract:
A current sensor can indirectly measure a sensed current by directly measuring static perturbing AC magnetic fields with magnetoresistance elements, the perturbing magnetic fields generated by perturbing coils. The sensed current can be indirectly measured by modulating or changing sensitivities of the magnetoresistance elements in a way that is directly related to the sensed current.
Abstract:
A magnetoresistance element assembly has two stacks of material layers with respective reference layers and respective bias layers that have relative magnetic directions that are not perpendicular to each other. Bias layers in the two stacks have bias magnetic directions that oppose each other. Linear range is increased.
Abstract:
A magnetoresistance element has a pinning arrangement with two antiferromagnetic pinning layers, two pinned layers, and a free layer. A spacer layer between one of the two antiferromagnetic pinning layers and the free layer has a material selected to allow a controllable partial pinning by the one of the two antiferromagnetic pinning layers.
Abstract:
In one aspect, a system includes a master component having a communication node; and a plurality of slave components. Each slave component has a bidirectional node. The slave components are configured to each store data in response to a trigger signal received at the bidirectional node from the communication node.