Abstract: Various means for improvement in signal-to-noise ratio (SNR) for a magnetic field sensor are disclosed for low power and high resolution magnetic sensing. The improvements may be done by reducing parasitic effects, increasing sense element packing density, interleaving a Z-axis layout to reduce a subtractive effect, and optimizing an alignment between a Z-axis sense element and a flux guide, etc.

Abstract: Disclosed is a MTJ sensing circuit for measuring an external magnetic field and including a plurality of MTJ sensor elements connected in a bridge configuration, the MTJ sensing circuit having an input for inputting a bias voltage and generating an output voltage proportional to the external magnetic field multiplied by the bias voltage and a gain sensitivity of the MTJ sensing circuit, wherein the gain sensitivity and the output voltage vary with temperature; the MTJ sensing circuit further including a temperature compensation circuit configured to provide a modulated bias voltage that varies as a function of temperature over a temperature range, such that the output voltage is substantially constant as a function of temperature. Also disclosed is a method for compensating the output voltage for temperature.

Abstract: Various means for improvement in signal-to-noise ratio (SNR) for a magnetic field sensor are disclosed for low power and high resolution magnetic sensing. The improvements may be done by reducing parasitic effects, increasing sense element packing density, interleaving a Z-axis layout to reduce a subtractive effect, and optimizing an alignment between a Z-axis sense element and a flux guide, etc.

Abstract: Various means for improvement in signal-to-noise ratio (SNR) for a magnetic field sensor are disclosed for low power and high resolution magnetic sensing. The improvements may be done by reducing parasitic effects, increasing sense element packing density, interleaving a Z-axis layout to reduce a subtractive effect, and optimizing an alignment between a Z-axis sense element and a flux guide, etc.

Abstract: Disclosed is a MTJ sensing circuit for measuring an external magnetic field and including a plurality of MTJ sensor elements connected in a bridge configuration, the MTJ sensing circuit having an input for inputting a bias voltage and generating an output voltage proportional to the external magnetic field multiplied by the bias voltage and a gain sensitivity of the MTJ sensing circuit, wherein the gain sensitivity and the output voltage vary with temperature; the MTJ sensing circuit further including a temperature compensation circuit configured to provide a modulated bias voltage that varies as a function of temperature over a temperature range, such that the output voltage is substantially constant as a function of temperature. Also disclosed is a method for compensating the output voltage for temperature.

Abstract: An out-of-plane tunneling magnetoresistive (TMR) magnetic field sensor includes a sense element that defines a sense plane and a flux guide configured to direct a magnetic field perpendicular to the sense plane into the sense plane. The magnetic field sensor further includes a first coil arranged in a first plane, a second coil electrically insulated from the first coil and arranged in a spaced-apart second plane, and drive circuitry operatively connected to the first coil and the second coil. The drive circuitry in a first mode energizes the first and second coils to generate respective first and second fields that combine to set a magnetization of the flux guide. The drive circuitry in a second mode energizes only the first coil to generate the first field so as to set a magnetization of the sense element without changing the magnetization of the flux guide.

Abstract: An electromagnetic sensing device with a package substrate, a first die mounted on the package substrate, and a second die mounted on the package substrate. The first die includes a first integrated circuit and a first magnetic core formed above the first integrated circuit. The first magnetic core has a first sensing axis parallel to a planar surface of the package substrate. The second die includes a second integrated circuit and a second magnetic core formed above the second integrated circuit. The second magnetic core has a second sensing axis orthogonal to the planar surface of the package substrate.

Abstract: A circuit has a magnetic sensor that produces an uncompensated magnetic sensor output signal. A temperature sensor produces an ambient temperature signal. A compensation circuit is connected to the magnetic sensor and the temperature sensor. The compensation circuit is configured to add a computed temperature compensation signal to the uncompensated magnetic sensor output signal to produce a magnetic sensor temperature compensated output signal that reduces thermally induced variation of the uncompensated magnetic sensor output signal.

Abstract: Various means for improvement in signal-to-noise ratio (SNR) for a magnetic field sensor are disclosed for low power and high resolution magnetic sensing. The improvements may be done by reducing parasitic effects, increasing sense element packing density, interleaving a Z-axis layout to reduce a subtractive effect, and optimizing an alignment between a Z-axis sense element and a flux guide, etc.

Abstract: An out-of-plane tunneling magnetoresistive (TMR) magnetic field sensor includes a sense element that defines a sense plane and a flux guide configured to direct a magnetic field perpendicular to the sense plane into the sense plane. The magnetic field sensor further includes a first coil arranged in a first plane, a second coil electrically insulated from the first coil and arranged in a spaced-apart second plane, and drive circuitry operatively connected to the first coil and the second coil. The drive circuitry in a first mode energizes the first and second coils to generate respective first and second fields that combine to set a magnetization of the flux guide. The drive circuitry in a second mode energizes only the first coil to generate the first field so as to set a magnetization of the sense element without changing the magnetization of the flux guide.

Abstract: Various means for improvement in signal-to-noise ratio (SNR) for a magnetic field sensor are disclosed for low power and high resolution magnetic sensing. The improvements may be done by reducing parasitic effects, increasing sense element packing density, interleaving a Z-axis layout to reduce a subtractive effect, and optimizing an alignment between a Z-axis sense element and a flux guide, etc.

Abstract: A circuit has a magnetic sensor that produces an uncompensated magnetic sensor output signal. A temperature sensor produces an ambient temperature signal. A compensation circuit is connected to the magnetic sensor and the temperature sensor. The compensation circuit is configured to add a computed temperature compensation signal to the uncompensated magnetic sensor output signal to produce a magnetic sensor temperature compensated output signal that reduces thermally induced variation of the uncompensated magnetic sensor output signal.

Abstract: A magnetic field sensor includes built-in self-test coils in a configuration to provide magnetic field stimulation along three axes, with a high field factor, and thus, reduce a power budget of the sensor and physical size of the self-test coils. The magnetic field sensor comprises a first bridge circuit including a plurality of sense elements configured to sense a magnetic field. The magnetic field sensor further comprises re-configurable self-test current lines coupled to a self-test source to perform high field, high power wafer and die level testing and trim, as well as low power in-situ characterization and calibration of the sensor. The self-test current lines may be routed to form a coil with multiple turns around the TMR elements.

Abstract: A method of fabricating fluxgate devices to measure the magnetic field in two orthogonal, in plane directions, by using a composite-anisotropic magnetic core structure.

Abstract: An electromagnetic sensing device with a package substrate, a first die mounted on the package substrate, and a second die mounted on the package substrate. The first die includes a first integrated circuit and a first magnetic core formed above the first integrated circuit. The first magnetic core has a first sensing axis parallel to a planar surface of the package substrate. The second die includes a second integrated circuit and a second magnetic core formed above the second integrated circuit. The second magnetic core has a second sensing axis orthogonal to the planar surface of the package substrate.

Abstract: A method of fabricating fluxgate devices to measure the magnetic field in two orthogonal, in plane directions, by using a composite-anisotropic magnetic core structure.

Abstract: In one embodiment, a TMR field sensor utilizes existing one or more self-test current lines in a configuration to extend magnetic field measurement range without sacrificing measurement sensitivity. The self-test current lines are energized to facilitate magnetic field measurement when the measured magnetic field reaches a threshold. The magnetic field created by self-test coil opposes an external magnetic field being measured to keep the net magnetic field within a desired range where the magnetic field sensor has linear output and desired sensitivity.

Abstract: A method of fabricating fluxgate devices to measure the magnetic field in two orthogonal, in plane directions, by using a composite-anisotropic magnetic core structure.

Abstract: Various means for improvement in signal-to-noise ratio (SNR) for a magnetic field sensor are disclosed for low power and high resolution magnetic sensing. The improvements may be done by reducing parasitic effects, increasing sense element packing density, interleaving a Z-axis layout to reduce a subtractive effect, and optimizing an alignment between a Z-axis sense element and a flux guide, etc.

Abstract: A magnetic field sensor is disclosed with built-in self-test coils in a configuration to provide magnetic field stimulation along three axes, with a high field factor, and thus, reduce a power budget of the sensor and physical size of the self-test coils. The magnetic field sensor comprises a first bridge circuit including a plurality of sense elements configured to sense a magnetic field. The magnetic field sensor further comprises re-configurable self-test current lines coupled to a self-test source to perform high field, high power wafer and die level testing and trim, as well as low power in-situ characterization and calibration of the sensor. The self-test current lines may be routed to form a coil with multiple turns around the TMR elements.