Tdk Corporation

Hidenori Ohata

Takahide Kurahashi

Yoshinori Matsumaru

Kazuaki Suzuki

Junichi Nakamura

Sakae Henmi

Makoto Hasegawa

Kenji Endou

Taro Miura

Katsuhiko Igarashi

Tomoaki Kawata

Akihito Watanabe

Disclosed herein is a nonreciprocal circuit element that includes a magnetic rotator disposed between first and second ground conductors, and a permanent magnet that applies a DC magnetic field to the magnetic rotator. The magnetic rotator includes a first ferrite core having a first surface covered with the first ground conductor, a second ferrite core having a second surface covered with the second ground conductor, a first center conductor directly fixed to a third surface of the first ferrite core positioned opposite to the first surface, and a second center conductor directly fixed to a fourth surface of the second ferrite core positioned opposite to the second surface.

Nonreciprocal circuit element, manufacturing method of the same, and communication apparatus using the same

Disclosed herein is a nonreciprocal circuit element that includes a permanent magnet, a magnetic material having an insulating property, a magnetic rotator sandwiched between the permanent magnet and the magnetic material, and an external terminal. The magnetic rotator includes a center conductor connected to the external terminal, and first and second ferrite cores sandwiching the center conductor. The external terminal covers a side surface of the magnetic material without covering a side surface of the permanent magnet.

Nonreciprocal circuit element and communication apparatus using the same

Disclosed herein is a nonreciprocal circuit element that includes a magnetic rotator, and a permanent magnet that applies a DC magnetic field to the magnetic rotator. The magnetic rotator includes a center conductor, a first ferrite core laminated on the center conductor, and a dielectric provided in a gap formed between the center conductor and the first ferrite core.

Disclosed herein is a non-reciprocal circuit device that includes a mounting surface substantially parallel to a stacking direction, first and second side surfaces substantially vertical to the mounting surface and substantially parallel to the stacking direction, a first permanent magnet, a magnetic rotator stacked in the stacking direction with respect to the first permanent magnet, the magnetic rotator having a central conductor and at least first and second ports derived from the central conductor, a first external terminal provided on the first side surface and connected to the first port, and a second external terminal provided on the second side surface and connected to the second port.

Non-reciprocal circuit device and communication apparatus using the same

A technique for improving a circulator element for its temperature characteristic is provided. A circulator element including a garnet type ferrite material, and a permanent magnet for applying a direct-current magnetic field to the garnet type ferrite material, wherein Srepresents the saturation magnetization of said garnet type ferrite material at a temperature TSrepresents one at a temperature Tand Srepresents one at a temperature Tand Srepresents the saturation magnetization of said permanent magnet at a temperature TSrepresents one at a temperature Tand Srepresents one at a temperature Twhere TTTand the saturation magnetizations SSSSSand Sare relative values providing that the saturation magnetizations at the temperature Tis 1, and

Circulator element

A non-reciprocal circuit element includes a microstrip TM resonator (n is a positive integer) with a metal disk and branches projecting from the metal disk in a trigonally symmetric structure, and a ferrite magnetic body spontaneously magnetized and coaxially disposed on the microstrip TM resonator. The metal disk and the branches are formed on a non-magnetic dielectric board having a ground conductor on its bottom face. The ferrite magnetic body is arranged so that a position of an electric field node matches to one of the branches.

Non-reciprocal circuit element and millimeter-wave hybrid integrated circuit board with the non-reciprocal circuit element

A multilayer ceramic part of the invention comprises an internal conductor layer and a ceramic layer which are formed by co-firing. The internal conductor layer is formed of an electrical conducting material containing silver as a main component, and the ceramic layer is formed of an yttrium-iron-garnet based oxide magnetic material with silver added thereto. Thus, the multilayer ceramic part can be fabricated in high yields, even when its size is much more smaller than that of a multilayer ceramic part fabricated until now.

Multilayer ceramic part

A non-reciprocal circuit element includes a plurality of inner conductors intersecting with keeping insulation with each other, a shield conductor connected in common to one end of the inner conductors, and a capacitor connected between the shield conductor and a ground of the non-reciprocal circuit element, for adjusting only eigen values of in-phase excitation. Thus, smaller size, lighter weight and lower height can be attained and also temperature characteristics can be optionally adjusted without changing material used and without inviting increased insertion loss.

Growing community of inventors

Tokyo, Japan

Hidenori Ohata