Matsushita Electric Industrial Co., Ltd.

Narihiro Mita

Hiroyuki Nakamura

Toru Yamada

Shigeru Tsuzuki

Toshio Ishizaki

Yuki Satoh

Kazunori Nishimura

Hiroshi Kushitani

Riho Sasaki

A balanced type filter includes at least one balanced type terminal. At least one predetermined reactance element is connected between the balanced type terminal and another terminal. A parallel resonance circuit is formed by parasitic components existing between the balanced type terminal and the other terminal, and the reactance element. The other terminal is of balanced type or unbalanced type.

Surface acoustic wave filter, balanced type filter and communication device

A high-frequency hybrid switch module arranged applicable to at least two different communications systems includes two low pass filters (LPFs), two phase shifters, a field effect transistor (FET) switch including FETs, and two SAW filters. The FETs and the SAW filters are mounted on a layered assembly including the LPFs and an electrode pattern of the phase shifters. The module can have a small overall size, a low cost, and a small loss, while being protected from static electricity. The module requires small number of low-noise amplifiers at a signal receiving side.

High-frequency composite switch module

A longitudinal mode type surface acoustic wave filter comprising a first IDT electrode, second and third IDT electrodes, and first and second reflector electrodes are formed on a piezoelectric substrate. The upper electrode of the first IDT electrode is connected to one of balanced type terminals, and the lower electrode of the first IDT electrode is connected to the other balanced type terminal. Also, the lower electrode of the second IDT electrode is connected to an unbalanced type terminal, and the lower electrode is grounded. The lower electrode of the third IDT electrode is connected to the unbalanced type terminal, and the upper electrode is grounded.

An inter-digital transducer has a piezoelectric substrate; and an IDT (inter-digital transducer) electrode having a pair of upper bus bar electrode and lower bus bar electrode placed facing each other on the piezoelectric substrate and a plurality of electrode fingers placed on the piezoelectric substrate each being led out from either the upper bus bar electrode or the lower bus bar electrode toward the other bus bar electrode, wherein the IDT electrode is constructed of a plurality of divisional IDT electrodes and connected to a balanced type terminal.

Growing community of inventors

Hirakata, Japan

Narihiro Mita