Abstract: Method and apparatus for providing error compensation for a magnetic field sensing element in a three-phase motor. In embodiments, a driving angle is determined from zero-crossings of the magnet pole-pairs and error compensation levels for the pole-pairs is determined to reduce distortions in the motor current waveform.

Abstract: An apparatus comprises one or more substrates and one or more coils. At least one of the coils is configured to produce a first magnetic field that induces eddy currents in a conductive target, which generates a reflected magnetic field. One or more magnetic field sensing elements supported by the one or more substrates detect the reflected magnetic field. A conductive support structure supports the one or more substrates. The support structure includes a gap in an area adjacent to the one or more coils so that the support structure does not generate a reflected magnetic field in response to the first magnetic field.

Abstract: A switching voltage regulator with variable minimum off-time. The value of the minimum off-time may depend on the voltage across a bootstrap capacitor.

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 magnetoresistance element disposed upon a substrate can include a stack of layers. The stack of layers can include a first portion including a first bias layer structure for generating a first bias magnetic field with a first bias direction, and a first free layer structure disposed proximate to the first bias layer structure, wherein the first free layer structure is biased by the first bias magnetic field. The stack of layers can also include a second portion including a second bias layer structure for generating a second bias magnetic field with a second bias direction; and a second free layer structure disposed proximate to the second bias layer structure, wherein the second free layer structure is biased by the second bias magnetic field, and wherein the first bias direction and the second bias directions are opposite to each other.

Abstract: Methods and apparatus for transmitting signals that are magnetically latched at a receiver. In embodiments, a signal isolator comprises a transmitter and a receiver on separate die. Signal disruptions may be minimized. In embodiments, the transmitter and/or receiver can be monitored for proper operation.

Abstract: Apparatus including a regulator configured to generate a regulated output and a diagnostic circuit configured to generate a diagnostic signal indicative of whether the regulator is able to maintain regulation is described. The regulator includes an amplifier having a first input responsive to a reference voltage, a second input responsive to a feedback signal associated with the regulated output, and an output at which a control voltage is provided and further includes a pass element controlled by the control voltage and coupled to a node which the regulated output is provided. The diagnostic circuit is responsive to the control voltage and to the reference voltage to generate the diagnostic signal. The regulator may be a voltage regulator or a current regulator and in some embodiments, the diagnostic signal takes the form of a composite signal indicative of whether a voltage regulator and whether a current regulator can maintain regulation.

Abstract: A pressure sensor includes a chamber comprising a conductive portion and a deformable portion coupled to the conductive portion and susceptible to deformation in response to a pressure differential between an interior of the chamber and an exterior of the chamber; at least one coil responsive to an AC coil drive signal; at least one magnetic field sensing element disposed proximate to the at least one coil and to the conductive portion of the chamber and configured to generate a magnetic field signal in response to a reflected magnetic field generated by the at least one coil and reflected by the conductive portion; and a circuit coupled to the at least one magnetic field sensing element to generate an output signal of the pressure sensor indicative of the pressure differential between the interior of the chamber and the exterior of the chamber in response to the magnetic field signal.

Abstract: Methods and apparatus to control a three-phase BLDC motor using phase current and phase voltage at zero current detection and a driving current derived from a bus current, for example. The driving current can be combined with a difference angle with an output provided to a controller to control a speed of the motor.

Abstract: A method of determining an error condition in a magnetic field sensor can include receiving a first bridge signal, the first bridge signal generated by a first full bridge circuit. The method can also include receiving a second bridge signal, the second bridge signal generated by a second full bridge circuit. The method can also include determining a bridge separation from the first bridge signal and the second bridge signal. The method can also include comparing a function of the bridge separation to a threshold value. The method can also include generating an error signal indicative of the error condition or not indicative of the error condition in response to the comparing.

Abstract: An electronic circuit includes a driver circuit having an output terminal that can be coupled to a load to drive the load. A control circuit is coupled to the driver circuit for controlling the driver circuit. A transistor is coupled in series between the driver circuit and the output terminal. The transistor has a first terminal coupled to the driver circuit and a second terminal coupled to the output terminal. A biasing circuit is coupled to a gate terminal of the transistor and configured to provide a constant voltage to the gate terminal to bias the transistor to a conducting state to reduce the susceptibility of the electronic circuit to electromagnetic interference. The biasing circuit includes a voltage regulator, a Zener diode, and a capacitor. The Zener diode and capacitor are coupled to the gate terminal and a reference terminal.

Abstract: A magnetic field sensor includes a lead frame, a semiconductor die having a first surface in which a magnetic field sensing element is disposed and a second surface attached to the lead frame, and a non-conductive mold material enclosing the die and at least a portion of the lead frame. The sensor may include a ferromagnetic mold material secured to a portion of the non-conductive mold material. Features include a multi-sloped taper to an inner surface of a non-contiguous central region of the ferromagnetic mold material, a separately formed element disposed in the non-contiguous central region, one or more slots in the lead frame, a molded ferromagnetic suppression device spaced from the non-conductive mold material and enclosing a portion of a lead, a passive device spaced from the non-conductive mold material and coupled to a plurality of leads, and a ferromagnetic bead coupled to a lead.

Abstract: Systems, methods, and techniques described here provide for a hybrid electrically erasable programmable read-only memory (EEPROM) that functions as both a single polysilicon EEPROM and a double polysilicon EEPROM. The two-in-one hybrid EEPROM can be programmed and/or erased as a single polysilicon EEPROM and/or as a double polysilicon EEPROM. The hybrid EEPROM memory cell includes a programmable capacitor disposed on a substrate. The programmable capacitor includes a floating gate forming a first polysilicon layer, an oxide-nitride-oxide (ONO) layer having disposed over a first surface of the floating gate, and a control gate forming a second polysilicon layer with the control gate formed over a first surface of the ONO layer to form a hybrid EEPROM having a single polysilicon layer and a double polysilicon EEPROM. The single polysilicon EEPROM includes the first polysilicon layer and the double polysilicon EEPROM includes the first and second polysilicon layers.

Abstract: A method of calibrating a magnetic field sensor includes setting a first input signal at a first input node of a processor of the magnetic field sensor to a constant value. While the magnetic field sensor experiences a magnetic field, a first transition at an output node of the processor is measured. A second input signal at a second input node of the processor is set to the constant value. While the magnetic field sensor experiences the magnetic field, a second transition of at the output node of the processor is measured. An orthogonality error value is calculated based on a deviation of the first transition and the second transition. The first and/or second input signal is adjusted by modifying the first and/or second input signal by a function of the calculated orthogonality error value to compensate for the orthogonality error.

Abstract: Methods and apparatus for a DC-DC converter having input voltage feedforward for reducing the effects of input voltage signal transients. In embodiments, a feedback circuit receives an output voltage and generates a feedback signal and a modulation circuit receives the feedback signal and generates a control signal for a switching element for generating the output voltage, which is boosted from an input voltage. A feedforward module combines a slope compensation signal, the input voltage, and current information for an inductive energy storage element, which forms a boost circuit for generating the output voltage and generates a ramp signal to the modulation circuit. A duty cycle of the control signal is proportional to an impedance compensation input, inversely proportional to the slope compensation and the input voltage, and inversely proportional to the inductor current.

Abstract: Methods and apparatus for a signal isolator having first and second dies separated by a voltage barrier region, wherein transmit and receive paths of the first and second dies provide bi-directional transfer of feedback and/or diagnostic signals between the first and second die. In embodiments, transmitter refresh signals and receiver refresh signals are exchanged to detect fault conditions.

Abstract: A monitor circuit for monitoring a level of a first and second regulated source may monitor a voltage level of regulated voltages or a current level of regulated currents. In an embodiment, the monitor circuit includes circuitry responsive to a first regulated voltage and to a second regulated voltage. A first circuit responsive to the first regulated voltage and to the second regulated voltage generates a first error signal indicative of at least one of an overvoltage condition of the first regulated voltage and an undervoltage condition of the second regulated voltage. A second circuit responsive to the first regulated voltage and to the second regulated voltage generates a second error signal indicative of at least one of an undervoltage condition of the first regulated voltage and an overvoltage condition of the second regulated voltage. A method for monitoring the levels of first and second regulated sources is also provided.

Abstract: A filter with dynamic parameter generation may comprises an input to receive an unfiltered signal, an output to provide a filtered signal, a filtering circuit that filters the unfiltered signal to produce the filtered signal according to a transfer function having at least one dynamic parameter, and a dynamic parameter generator circuit. The dynamic parameter generator circuit comprises an input to receive the unfiltered signal, a signal processing circuit to estimate a level of dynamics of the unfiltered signal, a parameter generation circuit to generate the at least one dynamic parameter based on the estimated level of dynamics of the unfiltered signal, and an output to provide the at least one dynamic parameter.

Abstract: A magnetic field sensor includes a first magnetic field sensing element first generating a first signal having a first axis of maximum sensitivity, a second magnetic field sensing element for generating a second signal and having a second axis of maximum sensitivity, one or more detectors for receiving an output of the first magnetic field sensing element or the second magnetic field sensing element, and a processor that receives an output of the one or more detectors and uses the output of the one or more detectors to calculate a first constant Kc and a second constant Ks and then uses Kc and Ks to compensate for an orthogonality error between the first axis of maximum sensitivity and second axis of maximum sensitivity. The detectors include peak detectors and/or zero-crossing detectors that compare the output of the first input signal or the second input signal with a threshold or zero.

Abstract: An apparatus comprises a first measurement circuit having a first magnetic field sensing element to detect a measured magnetic field and produce a first signal representing the measured magnetic field, and a first signal processing circuit to process the first signal to produce a first processed signal. A second measurement circuit comprises a second magnetic field sensing element to detect a measured magnetic field and produce a second signal representing the measured magnetic field, and a second signal processing circuit to process the second signal to produce a second processed signal. A diagnostic processing circuit is coupled to receive the first signal and the second signal and configured to process the first signal during a first time period to produce a first diagnostic signal, and process the second signal during a second time period. A logic circuit determines if an error is present.