Murata Manufacturing Co., Ltd.

Hidekazu Kitamura

Masaaki Taniguchi

Masaki Takeuchi

Kazuhiro Inoue

An elastic wave filter device includes first and second inductance elements included in a laminated substrate and first and second elastic wave filter chips mounted on the laminated substrate by flip-chip bonding. The first and second inductance elements provided in the laminated substrate include first and second coil patterns, respectively, which are provided in a plane located at a certain height level in the laminated substrate. The second coil pattern is arranged in a region in which the first coil pattern is provided.

Elastic wave filter device

A circuit substrate includes resistive films are disposed on the surfaces of lands included in a circuit pattern and these resistive films are used as resistances connected in series to a capacitor. Therefore, the resistances are connected in series without increasing the inductance in the capacitor, and accordingly, a circuit having a small impedance variation with respect to frequency can be obtained. Therefore, it is possible to obtain a power supply circuit and so forth having stable operation and fast response.

Circuit substrate having resistive films connecting external terminals in series with lands

A laminated common-mode choke coil is disclosed in which the coupling characteristics of first and second coil electrodes are improved so as to reduce normal mode impedance. A first coil electrode and a second coil electrode are laminated across an insulating layer. The first coil electrode is formed in a spiral shape in an area from a first external electrode to a first through-hole electrode (point L). A second coil electrode is formed in a spiral shape in an area from a third external electrode to a second through--hole electrode (point K). Both coil electrodes are spirally overlapped with each other in an area from point B to point K. Three coil embodiments are also disclaosed.

Laminated common-mode choke coil

A coil component uses a magnetic material having a relative permeability of a specified value or more which permits deviations in inductance to vary within a narrow range, even if the magnetic substrate material has a relative permeability having large deviations. The coil component includes a pair of magnetic substrates, non-magnetic layers and a coil. The non-magnetic layers and the coil are laminated between the magnetic substrates. A relative permeability of a material of the magnetic substrates is set such that a combined magnetic resistance R of the magnetic substrates which define a closed series magnetic circuit including the pair of magnetic substrates and the non-magnetic layers, and a combined magnetic resistance R of the non-magnetic layers have a relationship: R >R

Coil component

A piezoelectric resonator includes a laminated structure having a piezoelectric laminate, at least one pair of electrodes and a substrate. The piezoelectric laminate includes at least one first piezoelectric layer having a positive temperature coefficient of a resonant frequency and at least one second piezoelectric layer which has a negative temperature coefficient of a resonant frequency. The at least one pair of electrodes interpose at least one of the first and second piezoelectric layers. The substrate supports the laminated structure and holds a portion of the laminated structure such that a suspended portion of the laminated structure vibrates in response to application of a voltage across the pair of electrodes.

Piezoelectric resonator

A laminated common-mode choke coil is disclosed in which the coupling characteristics of first and second coil electrodes are improved so as to reduce normal mode impedance. A first coil electrode and a second coil electrode are laminated across an insulating layer. The first coil electrode is formed in a spiral shape in an area from a first external electrode to a first through-hole electrode (point L). A second coil electrode is formed in a spiral shape in an area from a third external electrode to a second through-hole electrode (point K). Both coil electrodes are spirally overlapped with each other in an area from point B to point K. Three coil embodiments are also disclosed.

A coil element includes a composite member located on a first magnetic substrate, a second magnetic substrate disposed on the composite member and an adhesive layer located therebetween. The composite member includes coil patterns and insulating layers. The adhesive layer is composed of a material having a relative magnetic permeability of more than about 1.0. Alternatively, the insulating layers, excluding a portion which surrounds an overlapping region of coil patterns, are composed of a material having a relative magnetic permeability of more than about 1.0. Alternatively, the insulating layers are provided with holes in the approximate central regions of the insulating layers surrounded by the coil patterns, and the holes are filled with the material of the adhesive layer.

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Sagamihara, Japan

Hidekazu Kitamura