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.

Systems and methods for eliminating or mitigating T-effects on Hall sensors. A system may comprise a magnet-coil arrangement for providing a relative movement therebetween to obtain a relative position, a Hall sensor for sensing the relative movement, a temperature sensor located in proximity of the Hall sensor for providing temperature sensing, and a controller having two or more channels coupled to Hall sensor and to the temperature sensor and configured to control the relative movement and to provide, based on the temperature sensing, a temperature correction input to the Hall sensor for compensating a temperature effect on the Hall sensor sensing.

A system and method that can automatically select a frequency of a magnetic field in a magnetic tracking system. A magnetic tracking system emits an alternating magnetic field using a set of three frequencies. In the present approach, a transmitter is capable of generating multiple sets of three frequencies. A processor selects a first set of frequencies to use and causes the receiver to measure the amplitude of the magnetic field at those frequencies. In one embodiment, the frequency set having the lowest energy is selected. The processor then compares an estimated jitter at those frequencies to the actual jitter experienced using the frequencies. If the actual jitter exceeds the estimated jitter by a predetermined amount, the processor switches to a different set of frequencies and causes the receiver to measure the magnetic field at the new set of frequencies. The process may repeat using the additional sets of frequencies.

A magnetic sensor array device is comprised of an array of magnetic sensors arranged on a common semiconductor substrate to measure the multi-axis magnetic field of an arbitrary sized region at high speed with high spatial resolution and high magnetic resolution. This invention further improves a multi-axis magnetic sensor array device fabricated on a common semiconductor substrate with additional optimizations to provide for variable spatial resolution, variable magnetic resolution, and a novel secret key derivation.

A method is provided for sensing a magnetic field in a magnetic gradiometer of the kind in which pump light and light constituting an optical carrier traverse first and second atomic vapor cells that contain host atoms and that are separated from each other by a known distance. According to such method, the host atoms are prepared in a coherent superposition of two quantum states that differ in energy by an amount that is sensitive to an ambient magnetic field. Modulation of the optical carrier in the respective cells gives rise to sidebands that interfere to generate a beat frequency indicative of the magnetic field gradient. The host atoms are prepared at least in a mode that allows measurement of ambient magnetic field components perpendicular to the axis of the pump light. In such mode, the host atoms are spin-polarized by pump light while subjected to a controlled magnetic field directed parallel to the pump beam, and then the controlled magnetic field is adiabatically extinguished.

A semiconductor device includes a vertical Hall element provided in a first region of a semiconductor substrate, and having the first to the third electrodes arranged side by side in order along a first straight line; a circuit provided in a second region of the semiconductor substrate different from the first region, and having a heat source; and a second straight line intersecting orthogonally a current path for a Hall element drive current which flows between the first electrode and the third electrode. The second line passes a center of the vertical Hall element, and a center point of a region which reaches the highest temperature in the circuit during an operation of the vertical Hall element lies on the second straight line.

Methods and apparatus for prosing a sensor IC package having first and second sets of magnetic field sensing elements and a third set of magnetic field sensing elements located between the first and second positions, wherein the first, second, and third sets of magnetic field sensing elements have a first axis of sensitivity and a second axis of sensitivity, wherein the first and second axes of sensitivity are orthogonal. The sensor IC package is positioned in relation to a target comprising a two-pole magnet and the first and second axes of sensitivity are perpendicular to an axis about which the target rotates. Differential signals are processed to determine an absolute position of the target. A first secondary angle position is generated from the first and third sets of magnetic field sensing elements.

An electromagnetic gradiometer that includes multiple torsionally operated MEMS-based magnetic and/or electric field sensors with control electronics configured to provide magnetic and/or electric field gradient measurements. In one example a magnetic gradiometer includes a first torsionally operated MEMS magnetic sensor having a capacitive read-out configured to provide a first measurement of a received magnetic field, a second torsionally operated MEMS magnetic sensor coupled to the first torsionally operated MEMS magnetic sensor and having the capacitive read-out configured to provide a second measurement of the received magnetic field, and control electronics coupled to the first and second torsionally operated MEMS magnetic sensors and configured to determine a magnetic field gradient of the received magnetic field based the first and second measurements from the first and second torsionally operated MEMS electromagnetic sensors.

Techniques are disclosed related to increasing prior limits imposed on MR gradient switching speed (dB/dt) without causing significant discomfort or severe pain perception to patients. The technique disclosed herein do so by modifying the pulsing gradient fields that are ordinarily available for MR imaging protocols. Doing so stimulates the peripheral nerves and thus enables a quick, reversible, and complete inhibition of action potential propagation through the stimulated region of tissue, referred to as a nerve conduction block.

An electronic system for a surgical instrument is disclosed. The electronic system comprises a main power supply circuit configured to supply electrical power to a primary circuit. A supplementary power supply circuit configured to supply electrical power to a secondary circuit. A short circuit protection circuit coupled between the main power supply circuit and the supplementary power supply circuit. The supplementary power supply circuit is configured to isolate itself from the main power supply circuit when the supplementary power supply circuit detects a short circuit condition at the secondary circuit. The supplementary power supply circuit is configured to rejoin the main power supply circuit and supply power to the secondary circuit, when the short circuit condition is remedied.