Murata Manufacturing Co., Ltd.

Kousuke Ishida

Katsuyuki Uchida

Hidetoshi Yamamoto

Haruhiko Ueno

A noise filter in which the resonance of noise can be prevented, which is small in size and inexpensive, and is useful especially in an electronic device of which the signal frequency exceeds 100 MHz. In the noise filter, ground conductors are arranged on the outermost layers of a laminate formed by lamination of magnetic sheets and firing thereof. Transmission lines and ground conductors are alternately arranged with the magnetic sheets being sandwiched between them, respectively. Signal electrodes connected to the transmission lines and ground electrodes connected to the ground conductors are formed on the outer surface of the laminate. Thus, a signal is transmitted through the transmission lines while the ground conductors are grounded, and therefore, high frequency noise can be attenuated by utilization of heat loss caused by the magnetic sheets.

Noise filter

A noise filter includes a plurality of magnetic sheets stacked one on another. The magnetic sheets are baked to form a layered product. A transmission line is arranged between the second and third magnetic sheets. The transmission line extends linearly in the longitudinal direction of the layered product. Two ground conductors have the second and third magnetic sheets therebetween. Signal electrodes connected to both ends of the transmission line are arranged adjacent to both ends, in the longitudinal direction, of the layered product. Grounding electrodes connected to the ground conductors are arranged in the middle positions, in the longitudinal direction, of the layered product. With the ground conductors being grounded, a signal passes through the transmission line, thus attenuating high-frequency noise using heat dissipation by the four magnetic sheets.

Growing community of inventors

Sagamihara, Japan

Kousuke Ishida