A communication system using vector and scalar potential is disclosed. The system uses field-free potentials signaling for many applications where the absence of shielding effects in sea water, plasma or other dense media due to the fact that the absence of (E,B) fields eliminates the possibility of induced charge and current response in the media being transited.

An electronic device is disclosed. The electronic device includes a device magnet designed to magnetically couple with an accessory device magnet. The electronic device further includes a display assembly and a magnetic field sensor configured to detect the accessory device magnet, thereby providing an indication that the accessory device is covering the display assembly. The electronic device further includes a shunt assembly designed to reduce the magnitude of the magnetic field of the device magnet, as determined by the magnetic field sensor, while allowing the magnetic field from the accessory device to sufficiently reach the magnetic field sensor. As such, the magnetic field sensor can be placed near the device magnet without triggering the magnetic field sensor. The electronic device may further include a microphone. Communication between the microphone and an integrated circuit can cease based on the magnetic field sensor detecting the accessory device magnet.

A magnetometer includes a sample signal device; a reference signal device; a microwave field generator operable to apply a microwave field to the sample signal device and the reference signal device; an optical source configured to emit light including light of a first wavelength that interacts optically with the sample signal device and with the reference signal device; at least one photodetector arranged to detect a sample photoluminescence signal including light of a second wavelength emitted from the sample signal device and a reference photoluminescence signal including light of the second wavelength emitted from the reference signal device, in which the first wavelength is different from the second wavelength; and a magnet arranged adjacent to the sample signal device and the reference signal device.

A circuit for sensing the driving current of a motor, the circuit comprising: a driver configured to generate a driving current for each phase of a multiple-phase motor, the instantaneous sum of all the driving currents being zero; a current sensor for each phase of the multiple-phase motor, each current sensor configured to measure the driving current of that phase and comprising a plurality of current sensor elements arranged with respect to each other such that each current sensor element has the same magnitude of driving current systematic error due to magnetic fields external to the driving current to be measured; and a controller configured to, for each phase of the multiple-phase motor, generate an estimate of the driving current of that phase to be the measured driving current of that phase minus 1/n of the total of the measured driving currents for all phases, n being the number of phases of the multiple-phase motor.

A magnetic sensor device includes a magnetic field converter that receives an input magnetic field input along a first direction and outputs an output magnetic field along a second direction, which is orthogonal to the first direction. A magnetic field detector is provided at a position where the output magnetic field is applied. A magnetic shield shields external magnetic fields along a third direction, which is orthogonal to both the first direction and the second direction. When viewed along the first direction, the magnetic field converter has a shape such that the length in the third direction is greater than the length in the second direction. When viewed along the first direction, the magnetic shield is provided at a position overlapping the magnetic field converter and the magnetic field detector, and the magnetic field transmittance of the external magnetic field is 1-30%.

The present disclosure provides magnetic sensor system that includes a magnetic sensor package comprising a magnetic single turn sensor and a magnetic multi-turn sensor, and a shield arrangement for shielding the magnetic sensor from stray magnetic fields. The shielding arrangement comprises a ferromagnetic tube that houses one or more magnets and connects to an end of rotating shaft, such that rotation of the shaft causes a corresponding rotation of the ferromagnetic tube and magnets. The magnetic sensor package is positioned on a surface of a PCB substrate, which is positioned in close proximity to the ferromagnetic tube and magnet arrangement. A shielding device is then arranged in close proximity to the magnetic sensor package, for example, on the opposite side of the PCB substrate or directly between the PCB substrate and the ferromagnetic tube, to provide additional shielding of any stray magnetic fields. The shielding device may be in the form of a disc or a ring of ferromagnetic material that has a higher level of magnetic conductivity.

An electronic circuit triage device diagnoses functionality of various electronic circuits of an electronic device. The electronic circuit triage device detects whether an electronic circuit is functioning properly by measuring a magnetic field pattern associated with the electronic circuit and comparing the magnetic field pattern to an expected magnetic field pattern. A magnetic sensor array includes non-packaged magnetic sensors disposed on a substrate. The non-packaged magnetic sensors can include bare dice, in one embodiment. In another embodiment, the magnetic sensors are formed directly on the substrate, such as by printing conductive traces on the substrate. In another embodiment, a magnetic sensor array includes a magnetic field converter configured to launch received magnetic fields along an axis corresponding to a magnetic sensor maximum sensitivity.

A magnetic sensor includes a magnetic field conversion unit that outputs an output magnetic field, a magnetic field detection unit that the output magnetic field can be applied, and a magnetic shield that shields external magnetic fields. The length of the magnetic field conversion unit in the third direction is greater than the length in the second direction. The magnetic shield overlaps the magnetic field conversion unit and the magnetic field detection unit. The magnetic field detection unit includes a Wheatstone bridge circuit in which a first bridge circuit including first and second magnetic field detection units and a second bridge circuit including third and fourth magnetic field detection units are connected in parallel. The first through fourth magnetic field detection units include two magnetoresistive units, and two of the magnetoresistive units have magnetoresistive effect elements that include magnetization fixed layers whose magnetization directions differ from each other.

A current sensor for detecting a magnitude of a current flowing through a measuring object has a magnetic core having a first magnetic core and a second magnetic core that is arranged magnetically in parallel to the first magnetic core, wherein the first magnetic core has a magnetic permeability that is higher than that of the second magnetic core in a first frequency band, and the first magnetic core has a magnetic permeability that is lower than that of the second magnetic core in a second frequency band, the second frequency band being higher than the first frequency band, and the current sensor detects the magnitude of the current in a frequency band that is constituted by combining the first frequency band and the second frequency band.

A first magnetic field generator generates a magnetic field intersecting a detection object being transported along a transport path. A second magnetic field generator opposite to the first magnetic field generator with respect to the transport path generates a magnetic field intersecting the detection object. A first magnetoresistive element between the first magnetic field generator and the transport path outputs, as a change in resistance, a change in magnetic flux density produced by transport of the detection object. The first and second magnetic field generators are different in a magnetic pole facing the transport path and are arranged with a center of the first magnetic field generator in a transport direction of the detection object and a center of the second magnetic field generator in the transport direction are located at mutually different positions. The first magnetoresistive element includes a first resistor and a second resistor arranged with spacing therebetween.