Tdk Corporation

Chengbin Lin

Shuichi Okawa

Koji Kuroki

Takeshi Oohashi

Toshiyasu Fujiwara

Takato Fukui

Makoto Kameno

Yukio Mitake

Kentaro Ushioda

A sensor chip of a magnetic sensor includes a magnetosensitive element, ferromagnetic films forming a magnetic gap overlapping the magnetosensitive element, and a passivation film provided on the ferromagnetic films so as to be filled in the magnetic gap. The ferromagnetic films each include a lower magnetic film and an upper magnetic film. The magnetic gap is configured such that a width between the upper magnetic films is larger than a width between the lower magnetic films. The material of the lower magnetic film is higher in permeability than the material of the upper magnetic film. With the above configuration, magnetic flux is efficiently applied to the magnetosensitive element, making it possible to achieve high detection sensitivity.

Magnetic sensor and manufacturing method therefor

Disclosed herein is a magnetic sensor that includes first and second magnetic layers opposed to each other through a magnetic gap, a magnetosensitive element disposed on a magnetic path formed by the magnetic gap, and a compensating coil wound around the first and second magnetic layers. The first magnetic layer, second magnetic layer, magnetosensitive element, and compensating coil are integrated in a sensor chip.

Magnetic sensor

An object of the present invention is to reduce leakage magnetic flux in a magnetic sensor provided with a sensor substrate and an external magnetic member. A magnetic sensor includes: a sensor substrate having an element forming surface on which magnetic sensing elements are formed, first and second side surfaces, and a back surface; a first external magnetic member provided between the first and second magnetic sensing elements; and a second external magnetic member having first and second parts and covering the first side surface and second side surface, respectively. The first and second parts of the second external magnetic member protrude from the element forming surface. According to the present invention, since the first and second parts of the second external magnetic member protrude from the element forming surface, leakage of magnetic flux between the first and second external magnetic members is reduced.

An object of the present invention is to enhance detection accuracy of a magnetic sensor having four bridge-connected magnetic sensing elements. A magnetic sensor includes magnetic layers-provided on a surface of the sensor substrateand bridge-connected magnetic sensing elements R-R. The magnetic layerincludes a main area Mand a converging area Shaving a width gradually reduced with increasing distance from the main area M, the magnetic layerincludes a main area Mand converging areas S, Seach having a width gradually reduced with increasing distance from the main area M, and the magnetic layerincludes a main area Mand converging areas S, Seach having a width gradually reduced with increasing distance from the main area M. The end portions of the converging areas S-Sand the end portions of the converging areas S-Sface each other, respectively, through gaps G-G, respectively. The magnetic sensing elements R-Rare disposed on magnetic paths formed by the gaps G-G, respectively. According to the present invention, detection accuracy is enhanced because a magnetic flux generated by current flowing in one magnetic sensing element does not affect the other sensing element.

A directional coupler including a main line having an input terminal and an output terminal, and a sub-line having a coupling terminal and an isolation terminal, the main line, the sub-line, the input terminal, the output terminal, the coupling terminal and the isolation terminal being disposed within a laminate, wherein the main line and the sub-line extend in a loop shape in parallel with and spaced apart from each other by a gap such that electromagnetic coupling is generated therebetween and such that the main line is positioned outside the sub-line on a coupling layer, the input terminal, the output terminal, the coupling terminal and the isolation terminal are disposed outside the main line, and the main line is interposed between the output terminal and the sub-line.

Growing community of inventors

Tokyo, Japan

Chengbin Lin