Abstract: The systems and methods described can reduce high order temperature coefficients on the Hall plate sensitivity. A temperature coefficient circuit may include a first amplifier to receive a first reference voltage generated in conjunction with a proportional to absolute temperature (PTAT) device and a second amplifier to receive a second reference voltage generated in conjunction with a complementary to absolute temperature (CTAT) device, the second amplifier having a second output node. A plurality of resistors may be disposed in a signal path between output node of the first amplifier and an output node of the second amplifier. The plurality of resistors may be coupled to at least one voltage-to-current converter through one or more resistors taps. The voltage-to-current converter may generate at least one current signal that can be operable to apply a multiplication factor or a division divisor to an amplifier coupled to the voltage-to-current converter.

Abstract: A magnetic field sensor for detecting motion of an object includes a magnet configured to generate a magnetic field and having a first surface adjacent to the object and a second surface distal from the object. The first surface of the magnet has a centerline axis substantially parallel to and disposed on the first surface, and the centerline axis is diagonal with respect to a motion axis substantially parallel to and disposed on the first surface and parallel to which the object moves. The magnetic field sensor also includes a semiconductor substrate disposed between the magnet and the object, the semiconductor substrate supporting a plurality of spaced magnetoresistance elements disposed along a sensing element axis substantially parallel to the centerline axis of the magnet and configured to generate a respective plurality of magnetic field signals in response to the motion of the object with respect to magnetic field.

Abstract: A magnetic field sensor includes a back bias magnet to generate a DC magnetic field. First and second magnetic field sensing elements of the magnetic field sensor are disposed proximate to at least one ferromagnetic surface of a ferromagnetic target object. The first and second magnetic field sensing elements generate first and second electronic signals, respectively, in response to first and second sensed magnetic fields corresponding to the DC magnetic field but influenced by the at least one ferromagnetic surface. The magnetic field sensor generates a difference signal that is a difference of amplitudes of the first and second electronic signals. The difference signal is indicative of a rotation measurement of an absolute relative rotation of the ferromagnetic target object and the magnetic field sensor about a rotation axis.

Abstract: A magnetic field sensor comprises at least one magnetic field sensing element configured to generate a measured magnetic field signal responsive to an external magnetic field; a diagnostic circuit configured to generate a diagnostic signal, wherein the diagnostic signal is not dependent on a measured magnetic field; a signal path comprising an amplifier and an analog-to-digital converter for processing the measured magnetic field signal to generate a sensor output signal indicative of the external magnetic field during a measured time period and for processing the diagnostic signal during a diagnostic time period; and a switch coupled to receive the measured magnetic field signal and the diagnostic signal and direct the measured magnetic field signal to the signal path during the measured time period and direct the diagnostic signal to the signal path during the diagnostic time period.

Abstract: Methods and apparatus for a magnetic sensor having a die and sensor circuitry formed in a device layer of the die with a coil integrated with the die to generate a magnetic field. A magnetoresistive magnetic field sensing element on the die detects changes in the magnetic field generated by the coil as a result of the presence of a ferromagnetic target. The sensor circuitry may process the changes in the magnetic field generated by the coil.

Abstract: In an embodiment, an electronic device comprises a shared electrical over-stress (EOS) protection circuit. The shared EOS protection circuit may be coupled between a power input terminal and ground terminal to provide an EOS current path from the power input terminal to the ground terminal, and coupled between the output terminal and the ground terminal to provide an EOS current path from the output terminal to the ground terminal. The electronic device may also include a power interruption mitigation circuit to provide power to the electronic device during interruptions or fluctuations in external power.

Abstract: In one aspect, a method includes processing a metal substrate, performing a first etch on a first surface of the metal substrate to form, for an integrated circuit package, secondary leads and a curved component having two primary leads and performing a second etch, on a second surface of the substrate opposite the first surface, at locations on the secondary leads and locations on the curved component to provide a locking mechanism. Each primary lead located at a respective end of the curved component.

Abstract: An integrated circuit can have a first substrate supporting a magnetic field sensing element and a second substrate supporting another magnetic field sensing element. The first and second substrates can be arranged in a variety of configurations. Another integrated circuit can have a first magnetic field sensing element and second different magnetic field sensing element disposed on surfaces thereof.

Abstract: In one aspect, a Hall Effect sensing element includes a Hall plate having a thickness less than about 100 nanometers an adhesion layer directly in contact with the Hall plate and having a thickness in a range about 0.1 nanometers to 5 nanometers. In another aspect, a sensor includes a Hall Effect sensing element. The Hall Effect sensing element includes a substrate that includes one of a semiconductor material or an insulator material, an insulation layer in direct contact with the substrate, an adhesion layer having a thickness in a range of about 0.1 nanometers to 5 nanometers and in direct contact with the insulation layer and a Hall plate in direct contact with the adhesion layer and having a thickness less than about 100 nanometers.

Abstract: In one aspect, a method includes etching a magnetic field sensor element covered by a bilayer hardmask. In another aspect, a method includes depositing a silicon nitride on a magnetic field sensor element, depositing a silicon dioxide on the silicon nitride, forming the bilayer mask by etching the silicon dioxide and etching the magnetic field sensor element partially covered by the bilayer hardmask. The magnetic field sensor element includes one of a giant magnetoresistance (GMR) element, a tunneling magnetoresistance (TMR) element or a magnetic tunnel junction (MTJ). The bilayer mask includes the silicon dioxide and the silicon nitride. In a further aspect, a sensor includes a magnetic field sensor element that includes one of a GMR element, a TMR element or a MTJ. The sensor also includes a bilayer hardmask disposed on the magnetic field sensor element. The bilayer mask includes a silicon dioxide and a silicon nitride.

Abstract: A structure having collocated magnetic field sensing elements can be used to simultaneously determine magnetic field and mechanical stress. A primary magnetic field sensing element generates a primary signal responsive to a magnetic field and a secondary magnetic field sensing element generates a secondary signal responsive to mechanical stress. A system includes a stress compensation module to receive the primary and signals, and to compensate for mechanical stress in the primary signal.

Abstract: A magnetic field sensor, a magnetic assembly, and a method provide circuits and techniques for or measuring one or more displacement angles of a magnet using magnetic field sensing elements. Applications include, but are not limited to, joysticks.

Abstract: Described embodiments provide a device configured to be coupled to a shared bus. The device includes a magnetic field sensing element to sense a magnetic field. Upon receiving a configuration command over the shared bus, the device determines whether a parameter of the sensed magnetic field meets a predetermined criteria. If the parameter of the sensed magnetic field meets the predetermined criteria, the device responds to the configuration command by applying one or more configuration settings. Otherwise, if the parameter of the sensed magnetic field does not meet the predetermined criteria, the device ignores the configuration command.

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 (BEST) circuits may be included.

Abstract: Methods and apparatus for determining a position of a rotor in motor, such as a three-phase motor by determining first and second ones of sectors in which a first one of the magnetic poles of the rotor may be positioned by driving phase pairs with complementary signals and examining a voltage of a floating one of the phases. Embodiments can further include driving first and second currents towards the first and second ones of the sectors and analyzing a time for each of the first and second currents to reach a threshold to identify which of the first and second ones of the sectors is aligned with the first one of the magnetic poles of the rotor.

Abstract: Methods and apparatus for determining a position of a rotor in a three-phase motor by determining first and second ones of sectors in which a first one of the magnetic poles of the rotor may be positioned by respectively driving phase pairs complementary signals and examining a voltage of a floating one of the phases. Embodiments can include applying torque to the motor by driving at least one phase pair with respective signals aligned in phase and unequal duty cycles to move the rotor a given amount from the rotor position in the first or second ones of the sectors for determining the position of the rotor.

Abstract: Embodiments provide systems and methods for determining a position of a gear shift lever of a vehicle. A ferromagnetic target object having selected characteristics influences a magnetic field generated by a back bias magnet. A magnetic field sensor includes magnetic field sensing elements disposed proximate to the target object. Each magnetic field sensing element generates an electronic signal in response to sensed magnetic fields. The gear shift lever moves among a plurality of gears of the vehicle. The magnetic field sensor selects a set of the magnetic field sensing elements to determine a magnetic field difference based on a difference of amplitudes between the electronic signals that is related to a current position of the gear shift lever. Characteristics of the target object enable the magnetic field sensor to detect the position of the gear shift lever. The characteristics include edges proximate to a perimeter of the target object.

Abstract: A magnetic field sensor includes a first magnetic field sensing element configured to produce a first signal representing a detected external magnetic field; a circular vertical hall element configured to produce a second signal representing an amplitude of the external magnetic field; and an error compensation circuit coupled to receive the first and second signal, compute an error value based on the amplitude of the external magnetic field, and apply the error value to the first signal to compensate for an error in the first signal.

Abstract: A back-biased magnetic field sensor can have one or more vertical Hall effect elements arranged within a substrate region of a substrate, wherein magnetic fields are oriented substantially vertical to the substrate within the substrate region when a ferromagnetic object is not proximate. When the ferromagnetic object becomes proximate, the magnetic field sensor can sense at least the proximity, and, in some embodiments, can also localize a position of the ferromagnetic object relative to the magnetic field sensor.

Abstract: Magnetic field sensors can sense speed of movement and direction of movement of a ferromagnetic object. Particular arrangements of magnetic field sensing elements within the magnetic field sensor can automatically cancel offset variations in the magnetic field sensing elements.