G01R33/0094

ARRAY OF MAGNETOMETERS OPERATING IN ZERO FIELD AND ASSOCIATED METHOD FOR CALIBRATING INTER-MAGNETOMETER COUPLINGS

The invention relates to a method for determining a coupling between magnetometers of an array of N magnetometers, for example with optical pumping, where each magnetometer comprises a field cancellation system capable of being activated to operate the magnetometer in zero field. This method comprises a first phase (P1) during which the N magnetometers are separated into N−1 magnetometers whose field cancellation system is deactivated and a measuring magnetometer whose field cancellation system is activated. This first phase comprises: the generation (GENj), by the magnetometers, of a plurality of reference magnetic fields of known amplitudes and distinct directions, the measurement (MESi), by the measuring magnetometer, of the ambient magnetic field on a plurality of measurement axes determination (CALCij) of coupling coefficients between the measuring magnetometer and each of the N magnetometers from said measurement and said known amplitudes.

MAGNETIC SENSOR ARRAY PROCESSING FOR INTERFERENCE REDUCTION

Current sensing techniques. In an example, a current sensing method includes: generating a first magnetic field measurement; generating a second magnetic field measurement; generating a frequency estimate of a current; calculating a root-mean-square (RMS) value of an estimated amplitude of the current; and generating a temperature estimate of an integrated circuit (IC) configured to perform the method. The method also includes generating a first weighting factor and a second weighting factor based on the frequency estimate, the RMS value, and the temperature estimate, the first weighting factor to control amplification of the first magnetic field measurement and the second weighting factor to control amplification of the second magnetic field measurement.

Magnetic sensor offset detection
11579210 · 2023-02-14 · ·

A digital compass with two or more multi-axis magnetometers and a processing element to determine a heading and detect any offset error in the heading is described. One electronic device includes first and second magnetometers. The second magnetometer can be disposed at least a specified distance or co-located and offset at least a specified angle from the first magnetometer. A processing device determines a magnetic field at the electronic device using a first output from the first magnetometer, detects an offset error in the magnetic field using a second output from the second magnetometer, and reports the offset error in the magnetic field.

Switch-mode power converters using hall effect sensors and methods thereof

System and method for transmitting and receiving. For example, the system includes a transmitter, one or more wires, and a receiver connected to the transmitter through the one or more wires. The transmitter is configured to generate a first current, and the receiver is configured to receive the first current. The receiver includes a coil, a Hall effect sensor, and a comparator, and the Hall effect sensor includes a first electrode and a second electrode. The coil is electrically isolated from the Hall effect sensor and configured to generate a magnetic field based at least in part on the first current flowing through the coil, and the Hall effect sensor is configured to sense the magnetic field and generate a first voltage at the first electrode and a second voltage at the second electrode. The comparator includes a first input terminal and a second input terminal.

Position detection element and position detection apparatus using same
11578996 · 2023-02-14 · ·

A position detection element includes an exchange coupling film having a large exchange coupling magnetic field and a position detection apparatus showing good detection accuracy in a high temperature environment. The position detection element includes an exchange coupling film composed of a fixed magnetic layer and an antiferromagnetic layer stacked on the fixed magnetic layer. The antiferromagnetic layer includes an X(Cr—Mn) layer containing X that is one or more elements selected from the group consisting of platinum group metals and Ni and containing Mn and Cr. The X(Cr—Mn) layer includes a PtMn layer as a first region relatively closer to the fixed magnetic layer and a PtCr layer as a second region relatively farther from the fixed magnetic layer. The content of Mn in the first region is higher than the content of Mn in the second region.

SENSOR AND INSPECTION DEVICE

According to one embodiment, a sensor includes an element part, and a control circuit part. The element part includes first and second elements. Each of the first and second elements includes a first magnetic element and a first conductive member. The control circuit part includes a first current circuit, a differential circuit, and a phase detection circuit. The first current circuit is configured to supply a first current to the first conductive member. The differential circuit is configured to output a differential signal corresponding to a difference of a first signal and a second signal. The first signal corresponds to a change in a first electrical resistance of the first magnetic element of the first element, The second signal corresponds to a change in a second electrical resistance of the first magnetic element of the second element. The phase detection circuit is configured to perform a phase detection of the differential signal.

Magnetic field sensor using different magnetic tunneling junction (MTJ) structures

The present disclosure relates to integrated circuits, and more particularly, to a highly sensitive tunnel magnetoresistance sensor (TMR) with a Wheatstone bridge for field/position detection in integrated circuits and methods of manufacture and operation. In particular, the present disclosure relates to a structure including: a first magnetic tunneling junction (MTJ) structure on a first device level; and a second magnetic tunneling junction (MTJ) structure on a different device level than the first MTJ structure. The second MTJ structure includes properties different than the first MTJ structure.

APPARATUS AND METHOD USING A PLURALITY OF MAGNETIC FIELD SENSITIVE DEVICES
20180003780 · 2018-01-04 · ·

An apparatus for magnetic field detection comprises a plurality of magnetic field sensitive devices comprising at least a first magnetic field sensitive device, a second magnetic field sensitive device and a third magnetic field sensitive device. The apparatus comprises a power source configured to provide a first supply current through the first magnetic field sensitive device and a second supply current independent of the first supply current through the second magnetic field sensitive device. The first to third magnetic field sensitive devices are coupled such that the first supply current flows through the first magnetic field sensitive device and not through the second magnetic field sensitive device, the second supply current flows through the second magnetic field sensitive device and not through the first magnetic field sensitive device, and a sum of the first supply current and the second supply current flows through the third magnetic field sensitive device.

SYSTEM AND METHOD FOR DETERMINING A CONFIGURATION OF A MEASUREMENT VOLUME
20230003550 · 2023-01-05 · ·

A method of determining a configuration of a measurement volume, the method may include: generating, by at least one transmitter, a transmitted magnetic field within the measurement volume; measuring, by at least one receiver positioned, a total magnetic field in the measurement volume at at least one receiver position and generating at least one receiver output signal; generating, by a processing unit, a measured dataset; comparing, by the processing unit, the measured dataset with at least one of at least two reference configuration datasets each for determined for one of at least two different configurations of the measurement volume; and identifying, by the processing unit, a reference configuration dataset of the at least two reference configuration datasets that corresponds to the measured dataset.

SIGNAL AMPLITUDE FEATURE-BASED METHOD FOR FAST RECONSTRUCTING A MAGNETIC PARTICLE IMAGING AND DEVICE
20230027988 · 2023-01-26 ·

The present disclosure includes: transforming a time-domain voltage signal collected by an MPI system device to a frequency domain; calculating a square root of a square sum of a real part and an imaginary part at each frequency point of a frequency domain signal; arranging acquired amplitudes in a descending order, and acquiring a screening threshold by an amplitude ratio method; screening an amplitude through the screening threshold and constructing frequency domain signal data; acquiring a row vector of a system matrix corresponding to each frequency point of the data, so as to construct an update system matrix; and solving, based on the frequency domain signal array and the update system matrix, an inverse problem in a form of a least square based on an L2 constraint to obtain a three-dimensional magnetic particle concentration distribution result, so as to achieve a fast reconstruction of the MPI system.