Abstract: A magnetic field sensor for sensing an absolute position of a target object can include one or more magnetic field sensing elements disposed proximate to a mechanical intersection of first and second portions of a target object, wherein the one or more magnetic field sensing elements are operable to generate a first magnetic field signal responsive to the movement of both the first and second portions. The magnetic field sensor can also include a position detection module operable to use the first magnetic field signal to generate a position value indicative of the absolute position. The magnetic field sensor can also include an output format module coupled to receive the position value and to generate an output signal from the magnetic field sensor indicative of the absolute position.

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 method can use a current sensor that can include a magnetic flux concentrator and a first magnetic field sensing element disposed proximate to the magnetic flux concentrator, the first magnetic field sensing element having a first maximum response axis, the first magnetic field sensing element operable to generate a first signal responsive to a first magnetic field proximate to the first magnetic field sensing element resulting from an electrical current passing through a conductor, wherein the magnetic flux concentrator is operable to influence a direction of the first magnetic field.

Abstract: A charge pump includes a first power source having a voltage VREG generated from a regulated and circuit-limiter supply, a second power source having a voltage VBRG and a top-off capacitor adapted to be charged to a voltage of the high of VREG or VBRG to a limit of a voltage clamp across the top-off capacitor.

Abstract: Methods and apparatus for a sensor system having a first magnetic field sensing element with first and second segments where the first and second segments are located at positions to generate magnetic field bias in opposite directions for reducing sensitivity due to misalignment of the first and second segments. A processing module is configured to receive an output of the magnetic field sensing element.

Abstract: A motor drive circuit for driving an electric motor includes a plurality of driver circuits, each one of the plurality of driver circuit comprising a high side transistor coupled to a low side transistor in a half bridge arrangement, wherein each one of the high side transistors and each one of the low side transistors has a respective control node and respective first and second current passing nodes, wherein the second current passing node of each of the high side transistors is coupled to the first current passing node of a respective one of the low side transistors at a respective junction node, wherein each one of the plurality of driver circuits is operable to drive a respective current out of a respective junction node into a respective winding of the electric motor. The motor drive circuit further includes a capacitor coupled to the first current passing node of each one of the high side transistors, the capacitor operable to hold a capacitor voltage.

Abstract: Magnetic field sensors and associated techniques use a Hall effect element in a current spinning arrangement in combination with a rippled reduction feedback network configured to reduce undesirable spectral components generated by the current spinning and other circuit elements.

Abstract: A magnetic field sensor comprises a magnetoresistance element with a variable conductivity that changes based on a function of a magnetic field strength and angle of an external magnetic field and a voltage across the magnetoresistance element. A circuit is included to monitor an electrical current through the magnetoresistance element during operation and to apply a constant voltage across the magnetoresistance element based on the monitored electrical current so that the variable conductivity does not change as result of a changing voltage across the magnetoresistance element.

Abstract: A method for synchronization of an input signal includes providing the input signal to a first signal path associated with a first clock and to a second signal path associated with a second clock, detecting an edge of the input signal by detecting values of the input signal along the first signal path at a first rising edge of the first clock and at a second rising edge of the first clock, detecting a value of the input signal along the second signal path at an edge of the second clock, and selecting the input signal from the first signal path or from the second signal path according to the detected value of the input signal along the second path when an edge of the input signal along the first path is detected.

Abstract: A joystick assembly for use with a device including a joystick surface and a first magnet having north and south magnetic poles includes a second magnet having north and south magnetic poles and a movable elongated shaft having first and second opposing ends arranged along a major axis of the shaft. The first end of the shaft is coupled to the second magnet such that movement of the shaft results in movement of the second magnet relative to the first magnet such that a line between centers of the north and south magnetic poles of the second magnet is movable relative to a line between the north and south magnetic poles of the first magnet. An attraction of the second magnet to the first magnet results in a restoring force upon the shaft, and the shaft and the second magnet are removable from the joystick surface.

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

Abstract: A sensor includes an output circuit configured to generate a sensor output signal based on an input signal having a logic high or low level, as may be provided by a Schmitt trigger circuit. During normal operation, the output switches between a first percentage of the supply voltage for logic high and a second percentage of the supply voltage for logic low. To convey a failure at the output, an output signal is output as either ground or the supply voltage when a fault is detected. As such, a fault can be communicated any time the output voltage is not equal to the first percentage or the second percentage of the supply voltage.

Abstract: A current sensor integrated circuit to sense a current through a resistor includes a substrate, a tub disposed in the substrate, an analog front end disposed in the tub and comprising an amplifier having inputs coupled across the resistor and a charging circuit configured to bias the analog front end and the tub to a bias voltage that is a predetermined offset voltage greater than a common mode voltage associated with the resistor. In embodiments, the analog front end is biased to a first bias voltage and the tub is biased to a second, different bias voltage.

Abstract: A magnetic field sensor has a plurality of magnetic field sensing elements and operates as a motion detector for sensing a rotation or other movement of a target object.

Abstract: A magnetic field sensor includes a plurality of magnetic field sensing elements operable to generate magnetic field signals indicative of a magnetic field associated with an object, a plurality of channels coupled to receive the magnetic field signals and configured to generate a respective plurality of phase separated channel signals, and an output circuit coupled to receive the plurality of phase separated channel signals and configured to generate a sensor output signal including distinguishable pulses associated with the plurality of phase separated channel signals. The sensor output signal may include a first plurality of pulses associated with a first one of the phase separated channel signals and having a first characteristic and a second plurality of pulses associated with a second one of the phase separated channel signals and having a second characteristic different than the first characteristic, such as different signals levels and/or different pulse widths.

Abstract: Systems, methods, and apparatuses for magnetic field sensors with self-test include a detection circuit to detect speed and direction of a target. One or more circuits to test accuracy of the detected speed and direction may be included. One or more circuits to test accuracy of an oscillator may also be included. One or more circuits to test the accuracy of an analog-to-digital converter may also be included. Additionally, one or more IDDQ and/or built-in-self test (BIST) circuits may be included.

Abstract: A magnetic field sensor for determining a position of a magnet, the position identified by one or more position variables can include: one or more magnetic field sensing element operable to generate one or more magnetic field measurements of the magnet and an associated one or more measured magnetic field variable values; a first module for identifying calculated magnetic field variable values associated with a plurality of positions of the magnet; a second module operable to perform an optimization process to determine a value of a distance function, the distance function using the one or more measured magnetic field variable values and the calculated magnetic field variable values; and a third module operable to determine the position of the magnet by associating the value of the distance function with corresponding values of the one or more position variables. A complimentary method can be used in the magnetic field sensor.

Abstract: A motor control system for reducing or eliminating current ripple error during current sampling comprises a motor having a plurality of phase coils, a motor driver circuit having a plurality of switches coupled to the plurality of phase coils to drive current through the phase coils, and a motor controller circuit configured to provide a plurality of output control signals coupled to the plurality of switches. A phase circuit modifies a first output control signal to produce a modified control signal that is out of phase with a second output control signal. A current measuring circuit is included to measure a current through the motor by measuring the current during a first time period when the first output control signal is active and measuring the current during a second time period when the modified control signal is active.

Abstract: A motor control system includes a motor; a motor and a motor control circuit coupled to the motor to provide power to the motor. The motor control circuit includes a power feedback loop having a power reference circuit to provide a reference power level and a power control circuit configured to provide a constant power level to the motor so that the motor operates with a substantially constant power output. The constant power level is proportional to the reference power level. Thus, the motor also provides substantially constant torque when the motor is at a constant speed.

Abstract: A magnetoresistance element (e.g. a spin valve) for detecting a changing magnetic field includes a pinning layer, pinned layer adjacent to the pinning layer, a spacer layer adjacent to the pinned layer, and a free layer adjacent to the spacer layer and arranged so that the spacer layer is between the pinned layer and the free layer. The pinned layer has a bias with a bias direction configured to reduce an effect of a static field on the detection of the changing magnetic field.