Abstract: Methods and apparatus for determining signal offset correction signals. In embodiments, first and second magnetic field sensing elements generate first and second channels that are in quadrature. Signal correction processing includes storing amplitudes of the first and second channel signals when an amplitude of the channel signals cross zero and determine an offset of the first and second channel signals based on the stored amplitudes.

Abstract: According to an embodiment, a magnetic field sensor includes: one or more magnetic field sensing elements; and a magnet structure to provide a bias magnetic field about the one or more magnetic field sensing elements, the magnet structure includes alternating magnetic layers and non-magnetic layers with at least three magnetic layers.

Abstract: Auto-calibrating current sensor integrated circuits (ICs) are configured for mounting at a position relative to a conductor. The auto-calibrating current sensor ICs can include a plurality of magnetic field sensing elements disposed at different locations within the integrated circuit, respectively, and can be configured to measure a magnetic field produced by a current carried by the conductor. The auto-calibrating sensors can include an electromagnetic model of the IC and the conductor. The model can be operative to determine a magnetic field at points in space due to a given current in the conductor at a known location of the conductor from the IC, and also the inverse situation of determining an unknown current and/or location of the conductor based on measurements of a magnetic field at known locations in space due to an unknown current in the conductor. Related auto-calibration methods are also described.

Abstract: Aspects of the present disclosure include galvanically-isolated (voltage-isolated) transformer-based integrated circuit (IC) packages providing cavities or spaces, which can, in some examples, be formed by preferentially heating the included magnetic core or a material coating the magnetic core. The provision of a space around the magnetic core allows the magnetic core to underdo size changes due to magnetostriction during use without being constrained or substantially constrained, thus, providing for improved magnetic performance. The circuits, ICs and IC packages and modules may include various types of circuits. In some examples, IC packages or modules may include a galvanically-isolated gate driver or other high voltage circuit.

Abstract: A method for use in a magnetic field sensor, including: in each of a plurality of calibration periods, generating a reference magnetic field based on a different one of a plurality of drive codes; storing, in a memory, a plurality of values of a reference magnetic field signal that is generated in response to the reference magnetic field, each of the values of the reference magnetic field signal being generated by sampling the reference magnetic field signal in a different one of the plurality of calibration periods; calculating a calibration gain coefficient based on the plurality of values of the reference magnetic field signal; and storing the calibration gain coefficient in the memory and using the calibration gain coefficient to adjust an output of the magnetic field sensor.

Abstract: Methods and apparatus for a desaturation circuit having a temperature compensated voltage threshold for protecting a power transistor, such as a FET. A comparator module has a first input compared to a voltage source associated with current through the FET and a second input coupled to the voltage threshold circuit. As a resistance of the FET changes due to temperature changes, the voltage threshold changes to compensate for the resistance change of the FET.

Abstract: A semiconductor device that includes an epitaxial layer having a first-type dopant, a first well having a second-type dopant, a base layer having the second-type dopant, a first metal layer comprising a first base terminal and an inner conductor, and a first via connecting the first base terminal to the first well. The base layer is formed within the epitaxial layer and in contact with the first well and at least one dielectric separates the inner conductor from the first base terminal, and the base layer.

Abstract: A sensor package comprising a lead frame, a current sensor die, and an interposer. The lead frame includes: (i) a primary conductor, (ii) a plurality of secondary leads, and (iii) a layer of dielectric material that is disposed between the primary conductor and the plurality of secondary leads. The current sensor die includes one or more sensing elements. The current sensor die is configured to measure a level of electrical current through the primary conductor of the lead frame. The interposer is disposed over the layer of dielectric material. The interposer includes a plurality of conductive traces that are configured to couple each of a plurality of terminals of the current sensor die to a respective one of the plurality of secondary leads.

Abstract: Systems, circuits, and methods provide controlled active DC bus discharge, such as for electric vehicles (EVs) or hybrid vehicles. Controlled active DC bus discharge can be provided using gate drivers to control operation of traction inverter switches, such as power transistors, to accomplish a charge bleeding function. Power transistors can be configured so that the gate is connected to the drain, thereby forcing the gate threshold voltage across drain and source. The gate of a power transistor can be actively driven between a threshold voltage and Miller plateau threshold voltage. As a result, several volts can be generated across the power transistor while current decays, therefore safely discharging the system DC bus.

Abstract: A heterogeneous sensor system includes a magnetic field sensor and an inductive sensor. A checker is configured to receive the magnetic field sensor output signal and the inductive sensor output signal and determine whether an error has occurred based on a comparison of the magnetic field sensor output signal and the inductive sensor output signal. Targets include at least a portion that is conductive and may include a ferromagnetic portion for back biased magnetic sensing. Additional features include on axis and off axis positioning of the sensors with respect to the target, multi-track targets for absolute position sensing, angle sensing and torque sensing configurations.

Abstract: A method, comprising: providing a target including: (i) a base having a through-hole formed therein that defines an inner perimeter of the base, the base having an outer side running around an outer perimeter of the base, and the base having an inner side running around the inner perimeter of the base, (ii) a first set of first conductive features that are coupled to the outer side of the base, each of the first conductive features extending outwardly, (iii) and a second set of second conductive features that are coupled to the inner side of the base, each of the second conductive features extending inwardly; and detecting an angular position of the target based on a first electrical angle that is associated with the first set of first conductive features and a second electrical angle that is associated with the second set of second conductive features.

Abstract: Methods and apparatus for an MR device having a ferromagnetic material, a heavy metal layer configured to flow a charge current, and an insulating layer between the ferromagnetic material and the heavy metal layer. The insulating layer is configured to electrically insulate and to magnetically couple the heavy metal layer and the ferromagnetic layer for generating a field like (FL) field in the ferromagnetic material in response to the charge current. In some embodiments, the MR device comprises a TMR device having a free layer or a reference layer oriented by the charge current. In other embodiments, the MR device comprises a GMR device.

Abstract: Methods and apparatus for automatic tuning of parameters for field-oriented control (FOC) of a BLDC motor with a controller with user input. Automatic tuning can include measuring electrical parameters comprising Phase resistance (Rs), Phase inductance (Ls), and Back-electromotive force (BEMF) constant (Ke). Automatic tuning can further include tuning of ac alignment and start-up processing, tuning of a current closed loop, and tuning of a speed closed loop.

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: Methods and apparatus for magnetic field sensor having a sample chopping with a shared ADC. A sensor may include receiving a chopping sequence for samples from first and second channels that share an analog-to-digital converter (ADC) in a magnetic field sensor. The samples for the first and second channel are timed with respect to a virtual sampling time (VST), such that a sum of the sample times for the samples for the first channel is equal to the VST, and a sum of the sample times for the samples for the second channel is equal to VST.

Abstract: Magnetoresistive element comprising a reference layer having a fixed reference magnetization; a ferromagnetic sense layer having a free sense magnetization having a stable vortex configuration that is orientable relative to the fixed reference magnetization in the presence of an external magnetic field; and a tunnel barrier layer between the reference layer and the sense layer and contacting a first side of the sense layer. The magnetoresistive element further comprises a hard magnetic layer arranged on a second side (212) of the sense layer opposed to the first side, the hard magnetic layer being configured to generate an interfacial magnetic coupling between the hard magnetic layer and the sense layer on the second side, such as to prevent chirality switching of the sense magnetization after the magnetoresistive element has been submitted to a heat treatment and an external magnetic field above vortex expulsion field.

Abstract: Methods and apparatus for motor startup with reduced acoustic noise include a startup module to generate a startup d-axis voltage during a startup interval and a startup q-axis voltage during the startup interval, wherein the startup interval ends at a time based on the observer error, and wherein the startup q-axis voltage increases during the startup interval. The startup module is configured to continuously linearly increase the speed of the motor during the startup interval. An observer generates a speed estimate, an angle estimate, and an observer error representative of a difference between an actual angle and the angle estimate. A voltage increment by which the startup q-axis voltage is increased during the startup interval is adjusted based on the observer error. The voltage increment can be equal to a constant value plus the observer error.

Abstract: In one aspect, a double-diffused metal oxide semiconductor (DMOS) includes a region of a semiconductor having a first region of a semiconductor having a first-type dopant, a first well having a second-type dopant, a dielectric within the first well, the dielectric having a bottom surface and a top surface opposite the bottom surface, a gate disposed on the top surface of the dielectric. The gate, the dielectric and the first well are configured to form a first reduced surface field (RESURF). The bottom surface of the dielectric has a first portion and a second portion, and the first portion of the bottom surface of the dielectric is closer to the top surface of the dielectric than the second portion of the bottom surface of the dielectric.

Abstract: In one aspect, a bridge includes at least eight sets of sub-arrays. Each one of the at least eight sets of sub-arrays forms a corresponding one magnetoresistance element. Each one of the at least eight sets of sub-arrays has a reference direction. The at least eight sets of sub-arrays are arranged in a matrix on a die. A reference direction of each one of the at least eight sets of sub-arrays is different from a reference direction of at least one other of the at least eight sets of sub-arrays.

Abstract: Aspects of the present disclosure include galvanically-isolated (voltage-isolated) transformer-based integrated circuit (IC) packages providing cavities or spaces for an included magnetic core to underdo size changes due to magnetostriction without being constrained or substantially constrained, thus, providing for improved magnetic performance. The circuits, ICs and IC packages and modules may include various types of circuits. In some examples, IC packages or modules may include a galvanically-isolated gate driver or other high voltage circuit.