Lem International Sa

Lem Intellectual Property Sa

Liaisons Electroniques-mecaniques Lem Sa

Dominik Schläfli

Wolfram Teppan

Stéphan Trombert

Benjamin Marcoz

Félix Buhlmann

Davide Azzoni

Fabien Millet

Jean-François Lanson

Luc Bossoney

Pascal Maeder

An open-loop electrical current transducer for measuring an electrical current flowing in a primary conductor, includes a magnetic circuit core with an air-gap, and a magnetic field sensing device positioned at least partially in the air-gap, the magnetic field sensing device including a circuit board, a first magnetic field detector in the form of an ASIC mounted on the circuit board, and a second magnetic field detector in the form of a conductive pick-up coil formed on two or more layers in or on the circuit board. The outputs of the first and second magnetic field detectors are connected to a signal processing circuit generating an output signal representative of the electrical current, the output of the ASIC representing a low frequency (LF) channel and the output of the pick-up coil representing a high frequency (HF) channel.

Current transducer

An electronic power switch drive module for a power semiconductor unit, comprising a gate drive and a current transducer mounted on one or more circuit boards, the gate drive comprising at least one circuit portion for controlling at least one transistor of a power semiconductor module of said power semiconductor unit, the current transducer configured to be coupled to an output of the power semiconductor module for measuring an output current of the power semiconductor module, said at least one circuit portion connected to an output potential of the output current to be measured. The current transducer comprises at least one magnetic field sensor, the current transducer being connected to said at least one circuit portion of the gate drive at said output potential in a non-isolated manner.

Electronic power switch drive module

A magnetic field sensor comprises a signal conditioning IC and a magnetic field sensor IC, the magnetic field sensor IC being mounted on and connected to the signal conditioning IC. The magnetic field sensor IC comprises a semi-conductor substrate with a sensor active layer disposed an outer facing side of the magnetic field sensor opposite the signal conditioning IC. The sensor active layer is connected to conductive vias that extend through the semi-conductor substrate from said outer facing side to an underside facing the signal conditioning IC, an underside of the conductive via being electrically interconnected to a connection pad on the signal conditioning IC via a chip-on-chip interconnection comprising a conductive bead connection and a solder connection.

Magnetic field sensor on integrated circuit

Current transducer comprising a section of a primary conductor and a magnetic field gradient sensor mounted in proximity to the primary conductor configured to measure a magnetic field gradient in a gradient measurement direction transverse to a direction of flow of a primary current flowing in the primary conductor. The current transducer further comprises a first lateral magnetic shim mounted adjacent a first outer side of the primary conductor, and a second lateral magnetic shim mounted adjacent a second outer side of the primary conductor, a major internal surface of the first and second magnetic shims facing the magnetic field gradient sensor and extending essentially parallel to the direction of flow of the primary current.

Electrical current transducer with magnetic field gradient sensor

Contactless voltage transducer for measuring voltages between at least two conductors of an alternating voltage conductor system, the transducer including two or more capacitive current measurement units, each said capacitive current measurement unit comprising

Contactless voltage transducer

Closed-loop current sensor comprising a magnetic circuit, a magnetic field sensor, and a compensation circuit configured to generate a magnetic field opposing a magnetic field created by an electrical current to be measured flowing in one or more primary conductors () extending through a central opening () of the magnetic circuit. The magnetic circuit comprises a magnetic core () made of at least two core parts () assembled together to form a substantially closed magnetic circuit, wherein a second branch () of the magnetic circuit comprises inner () and outer () wall portions joined by one or more lateral wall portions (') at least partially surrounding a cavity portion () receiving the magnetic field sensor () therein, the lateral and outer wall portions extending from one or both lateral edges of the inner wall portion.

Growing community of inventors

Nyon, Switzerland

Dominik Schläfli