G01R33/0017

Analog and digital co-design techniques to mitigate non-invasive spoofing attack on magnetic sensors

A structure for magnetic flux sensor conditioning is presented which partitions an input analog signal of unknown integrity into two: susceptible and insusceptible. The structure scrutinizes the susceptible signal partition, in view of additional guard sensor information, through a mixed-signal processing side-chain that employs a non-invasive physical magnetic attack detection algorithm. The side-chain either validates, or replaces with a best estimate, the susceptible signal partition, depending upon the absence or presence of attack, respectively. The structure finally recombines the scrutinized susceptible signal partition with the insusceptible signal partition. The result is an analog magnetic flux sensor signal that is robust against skillful, surreptitious, spoofing attacks. If unmitigated, such attacks may induce catastrophic consequences into systems relying upon the magnetic flux sensor.

STORAGE BATTERY INSPECTION DEVICE AND STORAGE BATTERY INSPECTION METHOD
20220349943 · 2022-11-03 ·

A storage battery inspection device includes: an energy storage control circuit that applies an alternating current to a storage battery; a magnetic sensor that senses a magnetic field component outside the storage battery and outputs a magnetic sensor signal indicating the sensed component; a canceling coil that generates a magnetic field component based on an input current to cancel out a magnetic field component generated by magnetization of a magnetic material in the storage battery; a feedback circuit that obtains, from the magnetic sensor signal, a low-frequency signal indicating a magnetic field component having a lower frequency than the alternating current, and applies the input current to the canceling coil based on the low-frequency signal; and a detection circuit that obtains, from the magnetic sensor signal, a detection signal indicating a magnetic field component having the same frequency as the alternating current.

MAGNETOMETER WITH INTEGRATED RESET COILS
20230089110 · 2023-03-23 ·

Disclosed is a magnetometer architecture that couples one or more coils to a magnetic yoke to allow the reset of the magnetic yoke and one or more magnetic field sensors simultaneously after, for example, exposure to a large stray magnetic field. Also, disclosed is a magnetometer architecture that integrates separate magnetic pole pieces offset from the yoke that are each wound by a reset coil to allow reset of the one or more magnetic field sensors.

CURRENT SENSOR DEVICE
20230086851 · 2023-03-23 ·

A sensor device includes a silicon substrate having an active surface; a first sensing area disposed near a first edge of the active surface of the silicon substrate such that the first sensing area has at least one first magnetic sensing element is made of a first compound semiconductor material and contact pads; and a second sensing area disposed near a second edge of the active surface of the silicon substrate, such that the second edge is substantially opposite to the first edge, such that the second sensing area has at least one second magnetic sensing element made of a second compound semiconductor material and contact pads. A processing circuit is disposed of in the silicon substrate and is electrically connected via wire bonds and/or a redistribution layer with the contact pads of the first and second sensing areas.

MAGNETIC SENSOR AND CURRENT SENSOR INCLUDING MAGNETO-RESISTANCE ELEMENT
20220349962 · 2022-11-03 ·

A magnetic sensor includes a magnetic-field detector including magneto-resistance elements, and a shield. Since the feedback coil is disposed so as to overlap with the magnetic-field detector, and the shield is disposed so as to overlap with the feedback coil, the cancellation field of the feedback coil makes it difficult to cause magnetization saturation. The shield is annular in shape as viewed from a direction normal to the shield. This allows maintaining the magnetic-field shielding action of the shield to enhance the effect of shielding the magnetic field in a direction perpendicular to the sensitivity.

HYDROGEN GAS SENSOR BASED ON ELECTRICALLY ISOLATED TUNNEL MAGNETORESISTIVE SENSITIVE ELEMENT

A hydrogen gas sensor utilizing electrically isolated tunneling magnetoresistive sensing elements is provided. The hydrogen gas sensor comprises: a substrate in an X-Y plane, tunneling magnetoresistive sensors located on the substrate, and a hydrogen sensing layer located on the tunnel magnetoresistive sensors. The hydrogen sensing layer and the tunneling magnetoresistive sensor are electrically isolated from each other. The hydrogen sensing layer includes a multi-layer thin film structure formed from palladium layers and ferromagnetic layers, wherein the palladium layers are used for absorbing hydrogen in the air that causes a change in the orientation angle of a magnetic anisotropy field in each of the ferromagnetic layers in the X-Z plane into an X-axis direction. The tunnel magnetoresistive sensors are used for detecting a magnetic field signal of the hydrogen sensing layer, wherein the magnetic signal determines the hydrogen gas concentration. This hydrogen gas sensor ensures measurement safety.

APPARATUS AND METHOD FOR CALIBRATING A MAGNETIC SENSOR SYSTEM USING AN INHOMOGENEOUS MAGNETIC FIELD SOURCE
20230090679 · 2023-03-23 ·

The invention relates to an apparatus as well as a method for calibrating a magnetic sensor system including at least one magnetic field source and one magnetic field sensor arrangement with several individual magnetic field sensors. Here, a plurality of individual measurements is performed, wherein each individual measurement provides a number of measurement values depending on the number of the individual magnetic field sensors. The magnetic field of the magnetic field source is varied at the location of the magnetic field sensor arrangement between two successive individual measurements. Based on the measurement values and by applying an optimization or estimation method, one or several magnetic field sensor-specific parameters and/or magnetic field source-specific parameters are determined, which are used as correction values for calibrating the magnetic sensor system. According to the invention, a magnetic field source is used that generates an inhomogeneous magnetic field.

MAGNETIC SENSOR
20230089851 · 2023-03-23 · ·

A magnetic sensor includes a substrate including a top surface, an insulating layer including an inclined surface, and a magnetic detection element disposed on the inclined surface. The magnetic detection element includes a first side surface and a second side surface. The first side surface is located at a position forward in a first direction that is one direction along the inclined surface. The second side surface is located at a position forward in a second direction that is another direction along the inclined surface. The magnetic detection element includes a first non-constant portion in which a gap between an upper end of the first side surface and an upper end of the second side surface becomes smaller along the longitudinal direction of the magnetic detection element.

MAGNETIC SENSOR

A magnetic sensor includes a plurality of resistor sections each including a plurality of MR elements, and a plurality of protruding surfaces each structured to cause the plurality of MR elements to detect a specific component of a target magnetic field. The plurality of MR elements are disposed dividedly in first to fourth areas corresponding respectively to the plurality of resistor sections. The plurality of protruding surfaces include a structural body extending across at least two of the first to fourth areas.

MAGNETIC SENSOR

A magnetic sensor includes a substrate including a top surface; an insulating layer disposed on the substrate, the insulating layer including first and second inclined surfaces each inclined with respect to the top surface of the substrate; and an MR element. The MR element is disposed on the first inclined surface or the second inclined surface. The MR element includes a first side surface including a first portion and a second portion, the first portion and the second portion having different angles with respect to the first inclined surface or the second inclined surface.