Abstract: Provided are a single-chip differential free layer push-pull magnetic field sensor bridge and preparation method, the magnetic field sensor bridge comprising: a substrate, a staggered soft magnetic flux concentrator array, and a GMR spin valve or a TMR magnetoresistance sensing unit array having a magnetic sensing axis in an X-direction on the substrate. A soft magnetic flux concentrator comprises sides parallel to an X-axis and a Y-axis, and four corners sequentially labeled as A, B, C and D clockwise from an upper left position. Magnetoresistive sensing units are located at gaps between the soft magnetic flux concentrators. Additionally, the magnetoresistive sensing units corresponding to the A and C corner positions and B and D corner positions of the soft flux concentrators are defined as push magnetoresistive sensing units and pull magnetoresistive sensing units, respectively.

Abstract: A single-chip high-magnetic-field X-axis linear magnetoresistive sensor with a calibration and an initialization coil, comprising a high magnetic field single-chip referenced bridge X-axis magnetoresistive sensor, a calibration coil, and an initialization coil, wherein the calibration coils are planar coils, and the initialization coils are planar or three-dimensional coils. The planar calibration coils and the planar initialization coils can be placed above a substrate and below the magnetoresistive sensor units, between the magnetoresistive sensor units and the soft ferromagnetic flux guides, above the soft ferromagnetic flux guides, or at gaps between the soft ferromagnetic flux guides. The three-dimensional initialization coil is wound around the soft ferromagnetic flux guides and magnetoresistive sensor units.

Abstract: The present invention discloses a magnetoresistive gear tooth sensor, which includes a magnetoresistive sensor chip and a permanent magnet. The magnetic sensor chip is comprised of at least one magnetoresistive sensor bridge, and each arm of the sensor bridge has at least one MTJ element group. The magnetoresistive gear tooth sensor has good temperature stability, high sensitivity, low power consumption, good linearity, wide linear range, and a simple structure. Additionally, the magnetoresistive gear tooth sensor has a concave soft ferromagnetic flux concentrator, which can be used to reduce the component of the magnetic field generated by the permanent magnet along the sensing direction of the MTJ sensor elements, enabling a wide linear range. Because it is arranged as a gradiometer, the magnetoresistive gear tooth sensor bridge is not affected by stray magnetic field; it is only affected by the gradient magnetic field generated by gear teeth in response to the permanent magnet bias.

Abstract: A magnetoresistive relay, comprising a substrate, a magnetic excitation coil, a magnetoresistive sensor, and switch integrated circuit which are placed on a substrate, which further includes an excitation signal input electrode, an excitation signal output electrode, a switch circuit positive output electrode, a switch circuit negative output electrode, a power input electrode, and a ground electrode. The ends of the magnetic excitation coil are each connected with the excitation signal input electrode and the excitation signal output electrodes. The signal from the magnetoresistive sensor is sent to the switch integrated circuit. The positive switch circuit output electrode and the switch circuit negative electrode are respectively connected with the switch integrated circuit. The power input ends and the ground ends of the switch integrated circuit and the magnetoresistive sensor are respectively connected with the power input electrode and the ground electrode.

Abstract: A single chip referenced bridge type magnetic field sensor for high-intensity magnetic field, the sensor comprises a substrate, a reference arm, a sense arm, shielding structures and attenuators. Wherein the reference arms and the sense arms comprise at least two rows/columns of reference element strings and sense element strings which comprise one or more identical electrically interconnected magnetoresistive sense elements; the reference element strings and the sense element strings are mutually interleaved, each reference element string is designed with a shielding structure on top of it, and each sense element string is designed with an attenuator on top of it. The magnetoresistive sensor elements can be AMR, GMR or TMR sensor elements. The shielding structures and attenuators are arrays of long rectangular bars composed of a soft ferromagnetic material, such as permalloy.

Abstract: An interdigitated Y-axis magnetoresistive sensor, comprising a substrate, and located on the substrate is a first comb-shaped soft ferromagnetic flux guide, a second comb-shaped soft ferromagnetic flux guide, and a push-pull magnetoresistive bridge sensing unit. It also may include a calibration and/or an initialization coil. The first and the second comb-shaped soft ferromagnetic flux guides are formed into an interdigitated shape. The gaps between a second comb tooth and two adjacent the first comb teeth are the first gap and the second gap. Furthermore, a pair of gaps are formed between the second come tooth and the base of the first comb as well as between the first comb tooth and the second comb tooth base. A push magnetoresistive unit string and a pull magnetoresistive unit string are alternately placed in the first gap and the second gap, respectively. The resulting magnetoresistive sensing unit senses the magnetic field along the X-axis.

Abstract: A rapid thermal processing method and apparatus used for programming the pinned layer of spintronic devices, the apparatus comprising a rapid thermal annealing light source, a reflective cover, a magnet, a wafer, and a substrate. The light source is used for heating the substrate. The reflective cover at least comprises a transparent insulating layer and a reflective layer. The magnet is used to produce a constant magnetic field. An antiferromagnetic layer on a wafer may be locally programmed by controlling the exposure time, for heating a specific area on the wafer to a temperature above the blocking temperature of the antiferromagnetic layer, and then turning off the magnetic field after the heating area has cooled in the presence of the applied magnetic field. This rapid thermal processing method is used to improve the spatial resolution of laser annealing. It provides excellent performance, and it is suitable for mass production.

Abstract: A push-pull X-axis magnetoresistive sensor, comprising: a substrate upon which an interlocked array of soft ferromagnetic flux concentrators and a push-pull magnetoresistive sensor bridge unit are placed. It further may comprise calibration coils and/or initialization coils. At least one of each of the soft ferromagnetic flux concentrators is present such that an interlocking structure may be formed such that there are alternately interlocked and non-interlocked gaps along the X direction. Push/pull magnetoresistive sensing unit strings are respectively located in the interlocked and non-interlocked gaps and are electrically connected to form a push-pull magnetoresistive bridge sensing unit. This magnetoresistive sensing unit is sensitive to magnetic field along the X direction.

Abstract: An integrated current sensor comprising a Z axis gradiometer and a lead frame primary coil, wherein the Z-axis gradiometer is a magnetoresistive Z-axis gradient sensor, comprising a substrate, with two elongated soft magnetic flux concentrators placed upon the substrate. The soft ferromagnetic flux concentrators are located above or below but displaced from a long-axis centerline equidistant from the magnetoresistive sensor strings, such that the combined magnetoresistive sensing unit detects the magnetic field perpendicular to the long-axis center line, and it is configured as a gradiometer sensor bridge. The lead frame serves as the primary coil, and the Z-axis gradiometer is placed above or below a cross-section of the current carrying portion of the lead frame, such that the current detection direction is parallel to the long-axis centerline. This sensor can detect currents of up to 5 to 50 A, it has low power consumption, small size, and fully integrated.

Abstract: A liquid level sensor system is disclosed for remotely monitoring the liquid level in a tank. The system comprises a first fixed portion with a first liquid level response unit, and a second fixed portion with a second liquid level response unit. A guide tube is inserted into the tank and attached to the bottom of the first fixed portion. The guide tube is provided with a multitude of ports, such that the liquid level in the guide tube is flush with the liquid level in the tank. The first liquid level response unit comprises a float floating up and down with the variation of the liquid level in the guide tube, a rotating shaft rotating around a relatively fixed axis of rotation in the up and down floating process of the float, and a permanent magnet. The second fixed portion is attached to the top of the first fixed portion. The second liquid level response unit comprises a PCB, a magnetoresistive angle sensor chip, and a control circuit electrically connected to the magnetoresistive angle sensor chip.

Abstract: A direct-current fan control chip comprises a magnetoresistive sensor, a controller, a driver and a substrate. The magnetoresistive sensor, the controller and the driver are integrated on the substrate. The sensing direction of the magnetoresistive sensor is perpendicular to or parallel to the surface of the direct-current fan control chip. The magnetoresistive sensor provides the controller with a rotor position signal, a rotor speed signal, and rotor a rotation direction signal for the controller. The controller outputs a control signal to the driver according to the received signals. After receiving the control signals, the driver outputs a drive signal. This control chip has the advantages of good temperature stability, good frequency response and so on.

Abstract: A single-package high-field magnetoresistive angle sensor, comprising at least one push-pull magnetoresistive bridge and soft magnetic flux attenuators located on the push-pull magnetoresistive bridge. The push-pull magnetoresistive bridge comprises a plurality of magnetoresistive sensor units. The magnetoresistive sensor units are of an MTJ or GMR type. Each magnetoresistive sensor unit comprises at least one pinned layer, one ferromagnetic reference layer, a nonmagnetic spacer layer, and a ferromagnetic free layer. The ferromagnetic free layer is a low aspect ratio oval or circle, which can make the intensity of magnetization of the ferromagnetic free layer align along an external magnetic field in any direction.

Abstract: A multiturn pulley liquid level sensor device for measuring a liquid level in a well and in a container, comprising a mechanical float which is fastened to a fastening rope and which can slide up and down. The fastening rope is installed on one or more pulleys, and as the float moves up and down, the pulley rotates back and forth. One pulley is mechanically coupled to one digital absolute magnetic rotation encoder device, and the encoder device is used for monitoring the total rotation angle of the pulley in real time. By way of using an algorithm, the total rotation angle of the pulley is converted into a distance from the bottom to calculate the height of a liquid level. A multiwheel encoder has two reading types, i.e., one is an electrical signal reading type, and the other is an optical signal reading type. The electronic output of said encoder may be used as input to an industrial control system, or be sent via communications link to a remote or the internet.

Abstract: A single chip Z-axis linear magnetoresistive sensor with a calibration/initialization coil comprises a single chip Z-axis linear magnetoresistive sensor, and a calibration coil and/or an initialization coil. The calibration coil and the initialization coil are planar coils or three-dimensional coils. The planar coils are located above a substrate and below a magnetoresistive sensing unit, between a magnetoresistive sensing unit and a soft ferromagnetic flux concentrator, above a soft ferromagnetic flux concentrator, or in a gap of the soft ferromagnetic flux concentrator. The three-dimensional coil is wound around the soft ferromagnetic flux concentrator and the magnetoresistive sensing unit.

Abstract: A direct-read meter capable of eliminating magnetic interference of adjacent rotating wheels, comprising N coaxial rotating wheel permanent magnets and corresponding magnetic angle sensors, a sampling element, a storage element, and a computation element, The magnetic angle sensors sense a linear superposition of the magnetic field from the intended permanent magnet rotating wheel and the interfering magnetic fields from the other rotating wheel permanent magnets; The sampling element samples the output signals of the N magnetic angle sensors to form a N*1 raw signal matrix [V/Vp]k(i)raw; The storage element stores an N*N correction matrix [Cij]; and the computation element computes the correction signal matrix [V/Vp]kcorr(i)=[V/Vp]k(i)raw?sum{C(i, j)*[V/Vp]k(j)raw}, thus eliminating the interfering magnetic field and permitting calculation of the rotation angle of the rotating wheel permanent magnets.

Abstract: A monolithic three-axis linear magnetic sensor and manufacturing method wherein the sensor comprises an X-axis sensor, a Y-axis sensor and a Z-axis sensor. The X-axis sensor comprises a referenced bridge and at least two X ferromagnetic flux guides. The Y-axis sensor comprises a push-pull bridge and at least two Y ferromagnetic flux guides. The Z-axis sensor comprises a push-pull bridge and at least one Z ferromagnetic flux guide. The bridge arms of the referenced bridge and push-pull bridge are each formed by one or more magnetoresistive elements that are electrically interconnected. The directions of the sensing axes and the directions of magnetization of the pinned layers of the magnetoresistive elements are all oriented along the X-axis. This manufacturing method comprises first depositing a magnetoresistive thin film on a wafer, and then performing several processes such as magnetic annealing, photolithography, etching, coating, and the like in order to realize a sensor.

Abstract: A high sensitivity push-pull bridge magnetic sensor, wherein the sensor comprises two substrates, magnetoresistive sense elements, push-arm flux concentrators, and pull-arm flux concentrators, wherein the magnetization directions of the pinning layers of the magnetoresistive sense elements on the same substrate are the same, but are opposite to the magnetization directions of the pinning layers of the magnetoresistive sense elements on the adjacent substrate, and the magnetoresistive sense elements on one substrate are electrically interconnected to form a push-arm of the bridge, and the magnetoresistive sense elements on the other substrate are electrically interconnected to form a pull-arm of the bridge. The magnetoresistive sense elements on the push-arm and pull-arm are aligned respectively in the gaps between two adjacent push-arm flux concentrators and two adjacent pull-arm flux concentrators.

Abstract: An automatic magnetic flow recording device, comprises a multitude of coaxially disposed hard magnetic rotating wheels wherein the hard magnetic rotating wheels are circular, and rotate with respect to each other by a predetermined transmission ratio. Each hard magnetic rotating wheel has at least one corresponding biaxial magnetoresistive angle sensor. The biaxial magnetoresistive angle sensors measure the angular positions of the hard magnetic rotating wheels within the range of 0-360 degrees. The biaxial magnetoresistive angle sensors comprise two single-axis linear magnetoresistive sensors, wherein the single-axis linear magnetoresistive sensors are an X-axis magnetoresistive sensor or a Z-axis magnetoresistive sensor. The X-axis magnetoresistive sensor of the hard magnetic rotating wheel measures a magnetic field component parallel to the tangent of the circumference of the hard magnetic rotating wheel.

Abstract: A biaxial magnetoresistive angle sensor with a corresponding calibration method for magnetic field error correction, comprising two single-axis magnetoresistive angle sensors for detecting an external magnetic field in an X-axis direction and a Y-axis direction that are perpendicular to each other, a unit for calculating a vector magnitude of the voltage outputs of the single-axis magnetoresistive angle sensors along the X axis and the Y axis in real time, a unit for calculating a difference between a known calibration vector magnitude and the measured vector magnitude, a unit for dividing the difference by the square root of 2 in order to calculate an error signal, a unit for adding the error signal to the X-axis output and the Y-axis output respectively or subtracting the error signal from the X-axis output and the Y-axis output in order to calculate the calibrated output signals of the X-axis and the Y-axis angle sensors, a unit for calculating an arc tangent of a factor obtained by dividing the calibrated

Abstract: The present invention provides a push-pull bridge-type magnetic sensor for high-intensity magnetic fields. The sensor comprises two substrates, magnetoresistive sensing elements, push arm attenuators, and pull arm attenuators. Magnetization directions of pinning layers of the magnetoresistive sensing elements located on a same substrate are parallel, and magnetization directions of pinning layers of the magnetoresistive sensing elements on different substrates are anti-parallel, wherein the magnetoresistive sensing elements on one substrate are electrically connected to one another to form push arms of a push-pull bridge, and the magnetoresistive sensing elements on the other substrate are electrically connected to one another to form pull arms of the push-pull bridge. The magnetoresistive sensing elements in the push arms and the pull arms are arranged in columns above or below the push arm attenuators and the pull arm attenuators.