Abstract: Clock monitors for circuits having a plurality of oscillators. The clock monitors produce an error indication when one oscillator is determined to be outside of a desired operating range or beyond a defined threshold with respect to a second oscillator. The clock monitors include a synchronizer configured to receive a clock signal from a first oscillator of the plurality of oscillators and synchronize the received clock signal with a second oscillator and to produce a synchronized clock signal. The clock monitors can include a counter configured to produce a count value based on synchronized clock signal. The clock monitors include comparison circuitry configured to receive the count value and produce an error indication when the count value is outside a predetermined range. The clock monitors may be used to ensure correct clock operation for different transition scenarios, e.g., turning on or off a certain clock or power domain.

Abstract: Methods and apparatus for canceling inductive coupling in a magnetic field sensing device having one or more Hall elements. A device can include a Hall element having a first pair of first and second voltage sensing terminals at diametrically opposed locations on the Hall element, and a second pair of third and fourth voltage sensing terminals diametrically opposed locations on the Hall element. A first mirror conductive path extends around a perimeter of the Hall element in a first direction a second mirror conductive path extends around the perimeter of the Hall element in a second direction so that the first and second mirror conductive paths are on opposite sides of the Hall element and are equal and opposite to cancel inductive coupling.

Abstract: In one aspect, an angle sensor includes a first linear sensor and a second linear sensor. A first magnetic-field direction of a target magnet measured by the first linear sensor is substantially equal to a second magnetic-field direction of the target magnet measured by the second linear sensor. The first linear sensor, the second linear sensor and the target magnet are on an axis. The angle sensor determines an angle of a magnetic field.

Abstract: In one aspect, manufacturing a magnetic-field angle sensor includes heating, to a first temperature, a substrate, which includes heating a first magnetoresistance (MR) element including a first type of antiferromagnetic material having a first Néel temperature and a first magnetization direction and heating a second MR element including a second type of antiferromagnetic material having a second Néel temperature and a second magnetization direction. The manufacturing also includes, after heating the substrate to the first temperature, applying a first magnetic field to the substrate in an x-direction to enable a first magnetization direction and a second magnetization direction to be in the x-direction, enabling a temperature of the substrate to be a second temperature and applying a second magnetic field to the substrate in a y-direction to enable the second magnetization direction to be in the y-direction while the first magnetization direction remains in the x-direction.

Abstract: In one aspect, a method includes manufacturing a magnetic-field angle sensor on a wafer. The manufacturing includes forming a cosine bridge that includes forming a first magnetoresistance (MR) element. The manufacturing also includes forming a sine bridge that includes forming a second MR element. Forming the first MR element includes using a process to reduce orthogonality errors between the sine bridge and the cosine bridge caused by anisotropy present in magnetic material in the first MR element.

Abstract: Systems, circuits, and methods provide self-calibration for magnetoresistance-based magnetic field sensors. Examples can include use of a closed loop acting as a feedback or calibration loop that is configured to process a reference signal applied to one or more magnetoresistance elements in a MR-based magnetic field sensor that also detects one or more external magnetic fields. The closed loop can adjust a bias voltage applied to the one or more magnetoresistance elements based on the reference signal. The calibration loop can accordingly provide for automatic or self-calibration of sensitivity of one or more magnetoresistance elements of the sensors to compensate for external factors affecting sensitivity of the one or more magnetoresistance elements.

Abstract: In one aspect, a method of manufacturing a magnetoresistance (MR) element having layers include ramping up a temperature of a reference layer of the MR element to an annealing temperature of the reference layer by increasing an amplitude of laser pulses applied to the reference layer over time to an amplitude that corresponds to the annealing temperature of the reference layer; applying a magnetic field to the reference layer; and maintaining the amplitude of subsequent laser pulses over time that have the amplitude that corresponds to the annealing temperature of the reference layer until at least the reference layer is annealed.

Abstract: Methods and apparatus for a signal isolator having enhanced creepage characteristics. In embodiments, an isolator includes a leadframe having first and second die paddles each having opposed first and second surfaces, a first die supported by the first surface of the first die paddle, and a second die supported by the first surface of the second die paddle. The first and second die paddles are configured enhanced creepage characteristics.

Abstract: A sensor including: a substrate having a first region and a second region; a first series of first magnetoresistive (MR) elements formed on the substrate, the first series of first MR elements including at least two first MR elements; and a second series of second MR elements that is coupled in parallel with the first series of first MR elements to form a bridge circuit, the second series of second MR elements being formed on the substrate, the second series of second MR elements including at least two second MR elements, each of the at least two second MR elements having a different pinning direction than each of the at least two first MR elements, wherein one of the at least two first MR elements and one of the at least two second MR elements are formed in the first region of the substrate and have different pinning directions.

Abstract: A sensor, comprising: a supporting member; a permanent magnet that is coupled to the supporting member; and a sensor die having a plurality of sensing elements and processing circuitry formed thereon, the plurality of sensing elements being arranged to generate one or more signals in response to a pattern of magnetic flux density that is produced by the permanent magnet and modulated by an application of force to a shaft, the processing circuitry being configured to map the one or more signals to a value of a force applied to the shaft, and output an indication of the value of the force, wherein the permanent magnet and the sensor die are encapsulated in an encapsulating material, the encapsulating material being used to form a package of the sensor.

Abstract: An integrated circuit package and method of fabrication are described. The integrated circuit package includes a lead frame having a first surface and a second opposing surface and a semiconductor die having a first, active surface in which circuitry is disposed and a second opposing surface attached to the first surface of the lead frame. A magnet attached to the second surface of the lead frame has a non-contiguous central region and at least one channel extending laterally from the central region. An overmold material forms an enclosure surrounding the magnet, semiconductor die, and a portion of the lead frame.

Abstract: A current sensor comprising: a substrate; a conductor that is disposed on or adjacent to the substrate; one or more sensing elements that are formed on the substrate, the one or more sensing elements being configured to generate one or more first signals in response to a magnetic field that is associated with the conductor; and electronic circuitry that is formed on the substrate, the electronic circuitry being configured to generate a second signal based on the one or more first signals, the second signal being indicative of a level of electrical current through the conductor, wherein the electronic circuitry includes a first instance of a component, a second instance of the component, and mixing circuitry that is configured to mix an output of the first instance with an output of the second instance to produce a mixed signal.

Abstract: According to some embodiments, a method for determining a fault status of a target system can include: receiving one or more magnetic field signals sensed by one or more magnetic field sensing elements of a sensor, the one or more magnetic field signals responsive to a magnetic field generated by a target object of the target system, the target object having repetitive motion; processing the one or more magnetic field signals to detect values of one or more parameters indicative of vibration of the target system; calculating deviations between the detected values and corresponding reference values of one or more parameters; determining a fault level of the target system based on the calculated deviations of one or more parameters; and generating an output signal indicating to the fault level.

Abstract: An apparatus, including: one or more first conductive layers; a plurality of second conductive layers that are electrically coupled to the first conductive layers, the first conductive layers and the second conductive layers being arranged to form a conductor, the first conductive layers being arranged to define a rift in the conductor, the rift being formed by using a plurality of through-holes that are situated above or below each other, each of the plurality of through-holes being formed in a different one of the second conductive layers, each of the plurality of through-holes being formed directly above or below a solid portion of at least one of the first conductive layers; and a dielectric material that is arranged to encapsulate, at least in part, the first conductive layers and the second conductive layers.

Abstract: A method to calculate performance of a magnetic element including a reference bilayer including a ferromagnetic reference layer having a reference magnetization and an antiferromagnetic layer pining the reference magnetization by exchange-bias, the antiferromagnetic layer including a metallic polycrystalline material having a grain volume distribution; the method comprising: measuring an exchange-bias field (Hex) of the antiferromagnetic layer as a function of temperature; fitting a grain volume distribution function to the measured exchange-bias fields (Hex) to determine parameters characterizing the volume distribution function; calculating a variation in the direction of the reference magnetization as a function of a direction of an exposure magnetic field (H); and calculating the exchange bias field (Hex) for any value of the in-plane exposure magnetic field (H).

Abstract: A method comprising: generating signals SA1 and SB1 by using a first sensor that is positioned at a first position relative to a rotating target, the signals SA1 and SB1 being generated in response to a magnetic field that is associated with the rotating target; generating signals SA2 and SB2 by using a second sensor that is positioned at a second position relative to the rotating target; and calculating a position of the rotating target based on a ratio of a first difference between the signals SA1 and SA2 and a second difference between the signals SB1 and SB2.

Abstract: Clock monitors for circuits having a plurality of oscillators. The clock monitors produce an error indication when one oscillator is determined to be outside of a desired operating range or beyond a defined threshold with respect to a second oscillator. The clock monitors include a synchronizer configured to receive a clock signal from a first oscillator of the plurality of oscillators and synchronize the received clock signal with a second oscillator and to produce a synchronized clock signal. The clock monitors can include a counter configured to produce a count value based on synchronized clock signal. The clock monitors include comparison circuitry configured to receive the count value and produce an error indication when the count value is outside a predetermined range. The clock monitors may be used to ensure correct clock operation for different transition scenarios, e.g., turning on or off a certain clock or power domain.

Abstract: A magnetic sensor device comprising a plurality of magnetic sensor elements; each magnetic sensor element including a magnetic tunnel junction including a reference layer having a reference magnetization, a sense layer having a sense magnetization and a tunnel barrier layer; the sense magnetization comprising a stable vortex configuration in the absence of an external magnetic field, the vortex having a core reversibly movable in a plane (P) of the sense layer according to an external magnetic field; the sense layer including a peripheral shape in the plane (P), the peripheral shape including an asymmetric edge portion; the magnetic sensor elements being arranged such that the edge portion of a magnetic sensor element is opposite to the edge portion of the adjacent magnetic sensor element.

Abstract: A magnetic field sensor configured to sense an angle of a magnetic field associated with a rotatable target includes a first magnetic field sensing structure configured to generate a first signal indicative of the magnetic field and a second magnetic field sensing structure configured to generate a second signal indicative of the magnetic field, wherein the first and second magnetic field sensing structures are configured to detect quadrature components of the magnetic field. A controller responsive to the first and second signals includes an angle tracking observer having a sine block and a cosine block operatively coupled to compute the angular position of the target using a control loop based in part on a non-orthogonality error term and a magnitude calculator that uses the sine block and the cosine block to compute a magnitude of the magnetic field.

Abstract: Methods and apparatus for motor control having low noise variable-high frequency signal injection for an electric motor. Different injection signals have different signal characteristics. One of the first and second injection signals is selected on a cycle-by-cycle basis as part of a direct voltage signal input to control an electric motor. The first and second signal characteristics are configured to reduce acoustic noise generated by an electric motor.