G01R33/0035

Position sensing system with improved accuracy and the method thereof

A position sensing system has a trim unit to trim hall voltages generated by a first sensor and a second sensor in response to an excitation current, to compensate a non-orthogonality of the first sensor and the second sensor.

Channel sensitivity matching

A sensor includes: a reference magnetic field generator configured to generate a reference magnetic field that is modulated at a first frequency, a first magnetic field sensing element that is configured to generate a first internal signal that is modulated at a second frequency, and a second magnetic field sensing element that is configured to generate a second internal signal that is modulated at the second frequency. A first amplifier is configured to receive the first internal signal and output a first amplified signal; and a second amplifier is configured to receive the second internal signal and output a second amplified signal. A gain adjustment circuit is configured to produce a gain adjustment signal and adjust a gain of at least one of the first amplifier and the second amplifier based on the gain adjustment signal.

Magnetic sensor
11662399 · 2023-05-30 · ·

A magnetic sensor that includes a Hall element; a switch circuit configured to switch a direction of a drive current supplied to the Hall element between a first direction and a second direction; a magnetic field detection circuit configured to execute a detection operation for detecting a target magnetic field acting on the Hall element, based on a first difference between a Hall voltage generated in the Hall element when the drive current is supplied to the Hall element in the first direction and a Hall voltage generated in the Hall element when the drive current is supplied to the Hall element in the second direction; and a test magnetic field generation circuit configured to generate a test magnetic field different from the target magnetic field in a test operation.

DEVICES AND METHODS FOR MEASURING A MAGNETIC FIELD GRADIENT
20230160979 · 2023-05-25 ·

A method of determining a gradient of a magnetic field, includes the steps of: biasing a first/second magnetic sensor with a first/second biasing signal; measuring and amplifying a first/second magnetic sensor signal; measuring a temperature and/or a stress difference; adjusting at least one of: the second biasing signal, the second amplifier gain, the amplified and digitized second sensor value using a predefined function f(T) or f(T, ΔΣ) or f(ΔΣ) of the measured temperature and/or the measured differential stress before determining a difference between the first/second signal/value derived from the first/second sensor signal. A magnetic sensor device is configured for performing this method, as well as a current sensor device, and a position sensor device.

METHODS AND SYSTEMS FOR DIAGNOSING MAGNETIC SENSORS

A method includes generating a reference voltage by periodically switching direction of current flow in a diagnostic sensor, where the reference voltage is a non-sinusoidal differential voltage of which an amplitude alternates between minimum and maximum values, and where the reference voltage includes a diagnostic sensor output voltage component responsive to an external magnetic field and a diagnostic sensor offset voltage component responsive to a mismatch of the diagnostic sensor. The method also includes amplifying the reference voltage to produce an amplified reference voltage, where the amplified reference voltage is a differential voltage having an amplifier offset voltage component. Additionally, the method includes demodulating the amplified reference voltage by filtering the diagnostic sensor offset voltage component and the amplifier offset voltage component to produce a demodulated voltage. Also, the method includes digitizing the demodulated voltage to produce a digitized voltage.

Superconducting quantum interference array receiver and method for digitally controlling magnetic flux bias thereof

A receiver for detecting at least one electromagnetic signal while the receiver is moving relative to the Earth's magnetic field, the receiver comprising: an SQUID array for generating an output that is a transfer function of SQUID array magnetic flux that is supplied from a combination of an oscillating magnetic field of the at least one electromagnetic signal, the Earth's magnetic field, and a bias magnetic field; a bias-tee configured to divide the SQUID array output into a DC signal and an RF signal; a memory store configured to store a plurality of voltage and flux bias values, wherein each voltage value has a corresponding flux bias value that results in maximum SQUID array sensitivity; and a logic circuit configured to find a voltage value in the memory store that most closely matches the DC signal, and to apply to the SQUID array a flux bias corresponding to the most closely matched voltage value.

Method for recalibrating a micromechanical sensor, and recalibrateable sensor

Recalibrating a micromechanical sensor. The sensor is assigned a signal processing device for correcting the sensor signal on the basis of at least one previously determined initial trim value that is selected such that, given a defined sensor excitation, a production-related deviation of the sensor signal from a target sensor signal is compensated. The method for recalibrating the sensor includes: applying a defined electrical test excitation signal to the sensor structure, acquiring the corresponding sensor response signal, ascertaining a trim correction value for the at least one initial trim value on the basis of a previously determined relation between the sensor response signal and the trim correction value, and determining at least one current trim value for correcting the sensor signal, the determination of the at least one current trim value taking place on the basis of the at least one initial trim value and the ascertained trim correction value.

SAFETY MECHANISM MONITORING OF AUTOCALIBRATED COMPENSATION PARAMETERS
20230073677 · 2023-03-09 ·

An autocalibration method includes generating at least one sensor signal in response to measuring a physical quantity; compensating the at least one sensor signal based on at least one compensation parameter to generate at least one compensated sensor signal; generating the at least one compensation parameter based on the at least one sensor signal or the at least one compensated sensor signal; comparing each of the at least one compensation parameter to a respective tolerance range; on a condition that each of the at least one compensation parameter is within its respective tolerance range, transmitting the at least one compensation parameter as at least one validated compensation parameter to be used for compensating the at least one sensor signal; and on a condition that at least one of the at least one compensation parameter is not within its respective tolerance range, generating a fault detection signal.

Synchronization of magnetic sensor sampling frequency for body pose tracking in artificial reality systems

Magnetic sensor synchronization techniques for pose tracking in artificial reality systems include managing and sending, by one or more primary magnetic sensors, a wireless synchronization signal to other magnetic sensors to trigger sensing sampling. The primary magnetic sensor may generate and send sensor data to a wireless data hub that operates as a sensor data collector and transmits data for pose tracking in the system. Each of the other (non-primary) magnetic sensors, in response to receiving the wireless synchronization signal, updates its sampling starting clock based on new synchronization timing. Each of the magnetic sensors sends generated sensor data to its corresponding primary sensor or wireless data hub according to a different schedule to avoid conflicts between the various magnetic sensors. The synchronization process may be repeated a number of times if a sensor fails to receive or respond to a synchronization signal.

Device that includes a sensor unit and a self-calibration function

A device that includes a sensor unit and a processing unit. The sensor unit is configured to detect at least one measured value at a predetermined point in time. The processing unit is configured to carry out a self-calibration of the device as a function of the detected measured value. A method for self-calibration of a device is also described.