Murata Manufacturing Co., Ltd.

Murata Mfg. Co., Ltd.

Toshimi Kaneko

Masahiko Kawaguchi

Yukio Sakamoto

Katsuji Matsuta

Hiromichi Tokuda

Tetsuya Morinaga

Hidetoshi Yamamoto

Yasuhiro Nakata

Kazuo Dougauchi

Takahiro Azuma

Masahiro Bando

Tetsuya Murakawa

Yukio Hata

Ryuichi Fujinaga

Yutaka Sasaki

Harufumi Mandai

Atsuo Senda

Tohru Kasanami

Kunisaburo Tomono

Toshio Hori

Takashi Tomohiro

Toshio Kawabata

Eiichi Maeda

Toshi Numata

Tetsuo Hatakenaka

Yoshio Hanato

Kiyomi Sasaki

Hideyuki Kashio

Takayuki Hirotsuji

Kiyoshi Nakano

Katsuhiro Misaki

Hiromichi Sakai

Toshiaki Ikeda

Takashi Makita

Kazumi Kido

Kazuya Nishimura

Toyoaki Tsunematsu

Junichiro Wata

An LC filter is disclosed which exhibits excellent attenuation characteristics in a high-frequency range and substantially preserves its self-inductance and Q-factor. The LC filter is constructed of a laminated block formed by laminating insulating sheets each provided with a coil conductor. The coil conductors are connected in series to each other through via-holes to form a coil. Input/output external electrodes and ground external electrodes are disposed on the surfaces of the laminated block. The insulating sheets are laminated in a direction perpendicular to the input/output external electrodes and parallel to the mounting surface. The coil is axially placed perpendicular to the input/output external electrodes and parallel to the ground external electrodes and the mounting surface. A distributed capacitance is generated between the coil and each of the ground external electrodes to form a capacitor.

LC filter with a parallel ground electrode

There is provided a chip type filter which can be made compact, allows the matching of input/output impedance, and has preferable characteristics. A ground electrode is formed on one side of a dielectric substrate, and spiral-shaped pattern electrodes are formed on the other side. Input/output electrodes are led out from intermediate portions of the pattern electrodes. Curved portions are formed between the input/output electrodes and the ends of the pattern electrodes. The ends of the pattern electrodes are positioned close to each other. Protective layers are formed on the ground electrode and pattern electrodes, which are laminated and integrated to form external electrodes. The ends of the pattern electrodes and the ground electrode are connected by one of the external electrodes.

Chip type filter with electromagnetically coupled resonators

A transformer which has a core, a wire for a primary coil and two wires for a secondary coil. The wire for a primary coil and one of the wires for a secondary coil are wound around a body of the core together, that is, are bifilar-wound. The other wire for a secondary coil is single-wound around the bifilar-wound wires. The two wires for a secondary coil are connected in series to form a secondary coil, and the wire for a primary coil forms a primary coil by itself.

Transformer with bifilar winding

A resonator 10 includes a first dielectric substrate 12. An earth electrode 14 is formed almost entirely on one main surface of the first dielectric substrate 12. A first pattern electrode 16 and a first drawing electrode 18 are formed on the other main surface of the first dielectric substrate 12. The first pattern electrode 16 and the first drawing electrode 18 are covered with an insulation layer 20. A second pattern electrode 22 and a second drawing electrode 24 are formed on the insulation layer 20. The second pattern electrode 22 and the second drawing electrode 24 are covered with a protecting layer 26. The earth electrode 14 is covered with a protecting layer 28. The earth electrode 14, the first pattern electrode 16 and the second pattern electrode 22 are connected with each other through a terminal electrode 30a. Terminal electrodes 30b and 30c are connected to the earth electrode 14. A drawing terminal electrode 32 is connected to the first drawing electrode 18 and the second drawing electrode 24.

Resonator with spiral-shaped pattern electrodes

A laminate type LC composite device which has two coil sections each of which is a laminate of coil conductors and insulating sheets and a capacitor section which is a laminate of capacitor conductors and dielectric sheets. The LC composite device has at least two coils, and the coils are coiled in mutually opposite directions.

Laminate type LC composite device having coils with opposing directions

A feedthrough electronic device which has an electronic element with a feedthrough hole and a center conductor which penetrates the electronic element. The center conductor is composed of a lead line portion and a spring portion which protrudes from the lead line portion and contacts with an inner periphery of the electronic element with pressure. A wide portion for preventing deformation is provided at the spring portion. A ferrite bead, a doughnut-shaped capacitor or a tubular capacitor can be used as the electronic element which has a feedthrough hole. The lead line portion of the center conductor and the spring portion can be produced separately or integrally.

Feedthrough LC filter with a deformation preventing spring

A laminate type LC composite device has a coil connected in series between an input electrode and an output electrode, and a capacitor connected in parallel between the input electrode and the output electrode. Further, a micro coil is connected to the coil in series. The coil has an inductance of L and a stray capacitance of C, and the micro coil has an inductance of L' and a stray capacitance of C'. The inductances L and L', and the stray capacitances C and C' fulfill the conditions: LC&gt;L'C', to thereby increase the high-frequency characteristics and the insertion loss in a high frequency area of the LC composite device.

Laminate type LC composite device having a micro coil

A resonator comprises two dielectric substrates. A ground electrode and a U-shaped pattern electrode are formed respectively on the two surfaces of the first dielectric substrate. A take-out electrode is drawn out at a certain distance from one end of the pattern electrode, and is connected to the take-out terminal electrode. A guard electrode is formed opposite to the other end of the pattern electrode. A shield electrode is formed on a second dielectric substrate. The pattern electrode, the ground electrode and the shield electrode are connected by a terminal electrode. In addition, the guard electrode, the ground electrode and the shield electrode are connected by a terminal electrode. A chip-type filter can be obtained by forming a plurality of pattern electrodes on an dielectric substrate, and coupling them electromagnetically.

Resonator and chip-type filter using it

A strip line filter has at least two strip lines and a common ground electrode, and on an end, has a solder ground terminal electrode and at least two link ground terminal electrodes at a distance from the solder ground terminal electrode. The solder ground terminal electrode is electrically connected with the common ground electrode, and the link ground terminal electrodes electrically connect each of the strip lines with the common ground electrode. Another strip line filter has at least two strip lines and a common ground electrode, and on an end, has a ground terminal electrode which has a solder portion and at least two arm portions extending from the solder portion. The ground terminal electrode is electrically connected with the common ground electrode via the solder portion and with the strip lines via the arm portions.

Strip line filter

One example of a high-frequency filter includes a dielectric substrate having a high dielectric constant. On one whole main face of the dielectric substrate, an earth electrode is formed. On the other main face of the dielectric substrate, two pattern electrodes are formed. The pattern electrodes have first parts formed in parallel at an interval, and second parts extended in crossing (non-parallel) directions. Also, on one main face of the dielectric substrate, input-output electrodes are respectively formed near the end parts of the pattern electrodes, and capacitors are respectively formed between the open end parts and the input-output electrodes.

High-frequency filter

An earth electrode and a spiral pattern electrode are formed on both surfaces of a dielectric plate. One end of the pattern electrode is connected to the earth electrode. The width of the pattern electrode is made narrow in proportion to going from one end toward the other end. An area ratio S2/S1 is 0.15 or more when defining an area of the pattern electrode as S1, and an area of center portion where the pattern electrode is not formed as S2. A take-out electrode is drawn out from the pattern electrode with a distance from the one end of the pattern electrode. A chip type filter is manufactured by forming plural pattern electrodes on the dielectric plate, and coupling the pattern electrodes electromagnetically.

Resonator and chip type filter using the resonator

A noise filter includes a plurality of resistance patterns arranged in parallel, and a ground pattern opposed to the resistance patterns via a dielectric substrate. Distribution capacitance is caused between the resistance patterns and the ground pattern. The function of the noise filter comes from the distribution capacitance and the resistance of the resistance patterns as the RC composite elements. The noise filters can be connected in plural. Noise can be eliminated without twisting the effective signal components in a compact noise filter.

Noise filter

Disclosed herein is a flexible wiring cable being provided on its forward end with a connecting portion to be connected with a connector, which comprises a base film, a wiring conductor provided on the base film, a dielectric member electrically connected with the wiring conductor in the connecting portion of the base film, and a ground electrode electrically connected with the dielectric member for forming a capacitor with the wiring conductor.

Flexible wiring cable

A laminate type line transformer. On one side of an insulating substrate, a primary coil section which is a laminate of a first coil pattern layer and a second coil pattern layer with an insulating layer in-between is provided. On the other side of the insulating substrate, a secondary coil section which is a laminate of a first coil pattern layer and a second coil pattern layer with an insulating layer in-between is provided. Both in the primary coil section and in the secondary coil section, conductors of the first coil pattern layer and conductors of the second coil pattern layer are electrically connected alternately via a hole made in the insulating layer.

Line transformer and manufacturing process thereof

A signal input device having a mutual inductor formed by a coil connected with a capacitor for a grounding cable in series and a coil connected with a capacitor for a signal cable in series, and a compensating capacitor connected with the series circuit composed of the capacitor and the coil on the grounding cable in parallel. The compensating capacitor serves to prevent occurrence of a voltage on the grounding cable, and accordingly only regular signals received by an antenna are transmitted. The mutual inductor prevents resonance of inductance of a lead terminal of the compensating capacitor with capacitance of the compensating capacitor.

Growing community of inventors

Nagaokakyo, Japan

Toshimi Kaneko