Alps Electric Co., Ltd.

Alps Green Devices Co., Ltd.

Nobuhiro Hayashi

Akira Takahashi

Kiyoshi Sato

Akihiro Makino

Eiji Umetsu

Toshinori Watanabe

Takashi Hatanai

Fumihito Koike

Yoshihiro Kanada

Kiyoshi Kobayashi

Tatsuya Kogure

A current measurement apparatus includes multiple GMR elements and a calculation unit. The multiple GMR elements each include a pinned magnetic layer having a pinned magnetization direction, and a free magnetic layer having a magnetization direction to be changed by an external magnetic field. The calculation unit obtains the magnitude of a current to be detected, from outputs of the multiple GMR elements. The multiple GMR elements are disposed in ring shape around a conductor through which the current to be detected flows, and are electrically connected so as to form a series variable resistor by using the multiple GMR elements. The magnetization directions of the pinned magnetic layers are pinned in the same direction when viewed from an extension direction of the conductor at each of the positions of the elements.

Current measurement apparatus having a series of magnetoresistive effect elements disposed in a ring shape

A thin film magnetic head includes an upper core layer and a lower core layer which are made of an Fe&mdash;M&mdash;O alloy, an Fe&mdash;M&mdash;T&mdash;O alloy or an NI&mdash;Fe&mdash;X alloy so that the upper core layer has a high saturation magnetic flux density, low coercive force and high resistivity, and the lower core layer has a lower saturation magnetic flux density than the upper core layer, low coercive force, high resistivity, and a low magnetostriction constant. Also the lower core layer is formed so that the thickness gradually decreases toward both side ends, and a gap layer can be formed on the lower core layer to have a uniform thickness. Since the lower core layer is formed by sputtering, a material having excellent soft magnetic material can be used, thereby enabling recording at high frequency.

Combination magnetoresistive/inductive thin film magnetic head and its manufacturing method

A thin film magnetic head includes an upper core layer and a lower core layer which are made of an Fe--M--O alloy, an Fe--M--T--O alloy or an NI--Fe--X alloy so that the upper core layer has a high saturation magnetic flux density, low coercive force and high resistivity, and the lower core layer has a lower saturation magnetic flux density than the upper core layer, low coercive force, high resistivity, and a low magnetostriction constant. Also the lower core layer is formed so that the thickness gradually decreases toward both side ends, and a gap layer can be formed on the lower core layer to have a uniform thickness. Since the lower core layer is formed by sputtering, a material having excellent soft magnetic material can be used, thereby enabling recording at high frequency.

Combination magnetoresistive/inductive thin film magnetic head and its

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Niigata-ken, Japan

Nobuhiro Hayashi