Tdk Corporation

Masami Itakura

Hideya Matsubara

Tomoyuki Goi

Takuya Adachi

Yuichiro Okuyama

Hitoyoshi Kurata

Hideo Watanabe

Masashi Iwata

Hideaki Fujioka

Kiichi Nakamura

Yasuhiko Atsumi

Youiti Kanagawa

A wireless power feeder has a power feed coil that performs a power feed by a non-contact method to a wireless power receiver having a power receive coil. A power source section supplies AC power to the power feed coil. A control section calculates a power transmission efficiency from the power feed coil to the power receive coil to control a power source section so that the power supply to the power feed coil is in a stopped or intermittent state when the power transmission efficiency is lower than a first determination reference value; is in a first power supply state when the power transmission efficiency is equal to or higher than the first determination reference value and lower than a larger second determination reference value; and is in a second power supply state when the power transmission efficiency is equal to or higher than the second determination reference value.

Wireless power feeder and wireless power transmission system

A high frequency module incorporates a layered substrate, a plurality of elements mounted on a top surface of the layered substrate, and a metallic casing that covers these elements. The plurality of elements mounted on the top surface of the layered substrate include a band-pass filter element. The band-pass filter element includes a plurality of conductor layers for band-pass filter and a plurality of dielectric layers for band-pass filter that implement a function of a band-pass filter, but does not include any conductor layer that functions as an electromagnetic shield. A conductor layer for grounding that the layered substrate includes and the casing are each opposed to the band-pass filter element, and thereby function as an electromagnetic shield for the band-pass filter element.

Band-pass filter element and high frequency module

A high frequency module comprises a switch circuit connected to two antenna terminals and two diplexers connected to the switch circuit. Each of the diplexers incorporates two band-pass filters (BPFs). Each of the diplexers further incorporates a capacitor provided between one of the BPFs and a node of signal paths and another capacitor provided between the other of the BPFs and the node.

High frequency module

A high frequency switch module comprises an antenna port, a plurality of transmission signal ports, a plurality of reception signal ports, a high frequency switch, a plurality of LPFs and a plurality of phase adjusting lines. The high frequency switch allows one signal port among the transmission signal ports and the reception signal ports to be selectively connected to the antenna port. The high frequency switch includes a field-effect transistor made of a GaAs compound semiconductor. Each of the phase adjusting lines connects the high frequency switch to each of the LPFs. Each of the phase adjusting lines adjusts a phase difference between a progressive wave of a harmonic resulting from a transmission signal and produced at the high frequency switch and a reflected wave resulting from reflection of the progressive wave from each of the LPFs such that the power of a composite wave made up of the progressive wave and the reflected wave is made lower at the point of the high frequency switch.

High frequency switch module and multi-layer substrate for high frequency switch module

A thick film complex electronic component mounted on a substrate including an inductance, capacitance and/or resistance by a conductive film and a magnetic film on a ceramic substrate is improved by novel magnetic film. The magnetic film is produced by depositing paste of a raw material of ferrite on the substrate, and the paste together with the substrate are sintered at a relatively low temperature in the range of 600.degree. C. and 1200.degree. C. The present magnetic film which is sintered after the raw material of ferrite is deposited on the ceramic substrate has higher permeability and is mechanically stronger.

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Tokyo, Japan

Masami Itakura