Allegro Microsystems, LLC

Commissariat À L'énergie Atomique Et Aux Énergies Alternatives

Commissariat a L'energie Atomique Et Aux Energies Alternatives

Alexander Latham

Bryan Cadugan

Michael C Doogue

Shaun D Milano

Claude Fermon

Maxwell McNally

William P Taylor

Rémy Lassalle-Balier

Myriam Pannetier-Lecoeur

Shixi Louis Liu

Wade Bussing

Jason Boudreau

Hernán D Romero

Loïc André Messier

Georges El Bacha

Simon Rock

Andreas P Friedrich

Paolo Campiglio

Sundar Chetlur

Harianto Wong

Noémie Belin

Natasha Healey

Evan Shorman

Paul A David

Gerardo A Monreal

Yannick Vuillermet

Michael J Gaboury

Craig S Petrie

David Jamie Haas

Alejandro Gabriel Milesi

Aaron Cook

Joseph James Judkins, Iii

Christian Feucht

Stephen Marshall

Rishikesh Nikam

Maxim Klebanov

Robert A Briano

Cory Voisine

Michael G Ward

Steven Daubert

David Toebes

Srujan Shivanakere

Till-Jonas Ostermann

Sina Haji Alizad

Neil Tan

Xavier Du Hamel De Milly

Kevin Buckley

A system, comprising a target, a first receiving coil array, and a second receiving coil array. The target includes: (i) a first array of conductive features that are arranged in a line or arc and separated from one another by voids, and (ii) a second array of conductive features that are arranged in a line or arc and separated from one another by voids, the conductive features in the first array being staggered with respect to the conductive features in the second array. The first receiving coil array is configured to sense a first magnetic field that is associated with the first array of conductive features. The second receiving coil array is configured to sense a second magnetic field that is associated with the second array of conductive features.

Position sensing method

A current sensor IC includes a lead frame having a die attach pad and elongated leads extending in a single direction with respect to the die attach pad, a semiconductor die having a first surface attached to the die attach pad and a second, opposing surface supporting magnetic field sensing elements, and a non-conductive mold material. A first portion of the mold material encloses the semiconductor die and the die attach pad, a second portion of the mold material encloses a portion of the elongated leads, and the mold material further includes a wing structure between the first portion and the second portion. In assembly, the first portion of the mold material extends into a cutout through a current conductor and the wing structure abuts a surface of the conductor. The current sensor can implement differential sensing based on signals from at least two magnetic field sensing elements.

Sensor package and system

Auto-calibrating current sensor integrated circuits (ICs) are configured for mounting at a position relative to a conductor. The auto-calibrating current sensor ICs can include a plurality of magnetic field sensing elements disposed at different locations within the integrated circuit, respectively, and can be configured to measure a magnetic field produced by a current carried by the conductor. The auto-calibrating sensors can include an electromagnetic model of the IC and the conductor. The model can be operative to determine a magnetic field at points in space due to a given current in the conductor at a known location of the conductor from the IC, and also the inverse situation of determining an unknown current and/or location of the conductor based on measurements of a magnetic field at known locations in space due to an unknown current in the conductor. Related auto-calibration methods are also described.

Auto-calibration for coreless current sensors

Systems and methods described herein are directed towards integrating a shield layer into a current sensor to shield a magnetic field sensing element and associated circuitry in the current sensor from electrical, voltage, or electrical transient noise. In an embodiment, a shield layer may be disposed along at least one surface of a die supporting a magnetic field sensing element. The shield layer may be disposed in various arrangements to shunt noise caused by a parasitic coupling between the magnetic field sensing element and the current carrying conductor away from the magnetic field sensing element.

Systems and methods for integrated shielding in a current sensor

Systems, methods, and apparatus for differential magnetic field torque sensors that include first and second magnetic targets for coupling to one or more rotatable shafts. The magnetic targets can include multipole ring magnets having a plurality of alternating magnetic domains. First and second differential magnetic field angular position sensors positioned proximate to the magnetic targets produce angular position of the targets and a processing unit is operative to receive an angular position from each of the first and second differential magnetic field angular position sensors and determine a difference between the angular positions. The difference corresponds to an angle between the targets, and the processing unit is operative to calculate, based on the angle, a torque applied to the one or more rotatable shafts.

Magnetic field differential torque sensor

In one aspect, a magnetic field current sensor includes an annihilation detector. The annihilation detector includes an annihilation bridge that includes magnetoresistance elements. The annihilation detector also includes a current bridge that includes at least two of the magnetoresistance elements, a first comparator configured to compare an output signal from the annihilation bridge and a second comparator configured to compare an output signal from the current bridge. An output of the annihilation detector indicates whether an annihilation exists in one or more of the magnetoresistance elements using at least one of the outputs signals of the first and second comparators.

Magnetic field current sensor to reduce stray magnetic fields

Differential magnetic field torque sensors include first and second magnetic field concentrators that guide magnetic flux to a magnetic field sensor from first and second magnetic field directors and a target, such as a multipole magnet assembly configured as a ring magnet. The magnetic field concentrators have pairs of sections that are interdigitated and configured adjacent to magnetic field sensing elements of the magnetic field sensor. The magnetic field directors can each have a plurality of teeth, which can be interdigitated and adjacent or proximate to the target. The magnetic field directors can be configured to be mounted as a unit to a rotatable shaft while the target can be configured to be mounted to a different rotatable shaft. The magnetic field concentrators and magnetic field sensor can be fixed while the magnetic field directors and target can rotate with respect to each other about a twist axis.

Magnetic field differential linear torque sensor

A sensor includes a sensing element configured to generate a sensing element output signal indicative of a sensed parameter and a signal path responsive to the sensing element output signal and having at least one of an adjustable gain or an adjustable offset, wherein the signal path is configured to generate a sensor output signal indicative of the sensed parameter. A supply voltage detector is configured to generate a supply voltage signal indicative of which of a plurality of voltage ranges a supply voltage of the sensor falls within and at least one of the adjustable gain or the adjustable offset is adjustable in response to the supply voltage signal.

Supply voltage configurable sensor

Methods and apparatus for providing a high isolation current sensor. In embodiments, a current sensor includes a leadframe having a current conductor first portion and a second portion, a magnetic field sensing element positioned in relation to the current conductor for detecting a magnetic generated by current flow through the current conductor, and a die supported by at least a portion of the first and/or second portions of the leadframe, wherein the first portion of the lead frame includes an isolation region aligned with a first edge of the die. In embodiments, a current sensor includes SOI processing and features to enhance active layer isolation.

High isolation current sensor

A magnetic field sensor includes at least one coil responsive to an AC coil drive signal; at least one magnetic field sensing element responsive to a sensing element drive signal and configured to detect a directly coupled magnetic field generated by the at least one coil and to generate a magnetic field signal in response to the directly coupled magnetic field; a processor responsive to the magnetic field signal to compute a sensitivity value associated with detection of the directly coupled magnetic field and substantially independent of a reflected magnetic field reflected by a conductive target disposed proximate to the at least one magnetic field sensing element; and an output signal generator configured to generate an output signal of the magnetic field sensor indicative of the reflected magnetic field.

Coil actuated sensor with sensitivity detection

A current sensor IC includes a unitary lead frame having a primary conductor with a first thickness and a secondary lead having a second thickness less than the first thickness. A semiconductor die adjacent to the primary conductor includes a magnetic field sensing circuit to sense a magnetic field associated with the current and generate a secondary signal indicative of the current. An insulation structure is disposed between the primary conductor and the die. A mold material encloses a first portion of the secondary lead and a second portion of the secondary lead that is exposed outside of the package has the second thickness. A method of manufacturing a current sensor IC includes providing a unitary lead frame sheet having a first thickness, decreasing a thickness of a portion of the sheet to provide a first portion with the first thickness and a second portion with a smaller thickness, and stamping the sheet to form a repeating lead frame pattern, with each pattern including a primary conductor formed from the first portion and secondary leads formed from the second portion.

Current sensor integrated circuit with a dual gauge lead frame

Methods and apparatus for linear inductive torque sensing that may include transmitting an AC magnetic field with a transmit coil toward a conductive target and receiving a field reflected by the conductive target with a receive coil, wherein the conductive target comprises first and second targets positioned with respect to each other and each shaped to linearly increase or decrease an amount of conductive area of the conductive target due to relative movement of the first and second targets which changes an amount of the field reflected by the conductive target. A signal from the receive coil can be processed to determine a relative position of the first and second targets corresponding to an amount of torque on an elongate member connected to the first and second targets. In other embodiments, a change in inductance of the transmit coil is measured to determine relative target position.

Linear inductive torque sensor

According to some embodiments, a device includes: a magnetic field current sensor magnetically coupled to a conductor and configured to generate a magnetic field signal having a magnitude responsive to a current flowing through the conductor; a shunt interface having first and second input terminals electrically coupled to ends of a shunt disposed along the conductor, the shunt interface configured to generate a shunt signal having a magnitude responsive to the current flowing through the conductor; and a diagnostic circuit configured to receive the magnetic field signal and the shunt signal and to generate a fault signal based on a comparison between the magnitude of the magnetic field signal and the magnitude of the shunt signal.

Integrated shunt and magnetic field current sensor

A current sensor integrated circuit (IC) includes a unitary lead frame having at least one first lead having a terminal end, at least one second lead having a terminal end, and a paddle having a first surface and a second opposing surface. A semiconductor die is supported by the first surface of the paddle, wherein the at least one first lead is electrically coupled to the semiconductor die and the at least one second lead is electrically isolated from the semiconductor die. The current sensor IC further includes a first mold material configured to enclose the semiconductor die and the paddle and a second mold material configured to enclose at least a portion of the first mold material, wherein the terminal end of the at least one first lead and the terminal end of the at least one second lead are external to the second mold material.

Current sensor integrated circuits

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Harvard, MA, United States of America

Alexander Latham