Murata Manufacturing Co., Ltd.

Kazuo Dougauchi

Toshimi Kaneko

Yukio Sakamoto

Masahiko Kawaguchi

Katsuji Matsuta

Junichiro Wata

Yoshinori Sugihara

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 coil assembly includes a first magnetic mother board, and a second magnetic mother board. A coil is formed on the first magnetic mother board and composed of stacked coil conductors and insulating layers. A recess or groove is formed in the second magnetic mother board and has a shape corresponding to the shape of the coil. The coil is closely fit into the recess so as to insure connection of the first and second magnetic mother boards. Direct connection of the first and second magnetic mother boards provides a completely closed magnetic path. The insulating layers have no magnetic materials so as to provide a better electromagnetic connection.

Coil assembly

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

An antenna connector which has a magnetic core, a signal line wound around the magnetic core at least once, a high-frequency appliance side terminal and an antenna side terminal. The magnetic core and the signal line form a common mode choke coil. The high-frequency appliance side terminal is electrically connected with a signal line of a television or the like, and the antenna side terminal is electrically connected with an antenna lead-in wire.

Antenna connector

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

Kazuo Dougauchi