Skyworks Solutions, Inc.

Taiyo Yuden Co., Ltd.

Fujitsu Media Devices Limited

Wisol Japan Co., Ltd.

Koichi Hatano

Masanori Ueda

Tokihiro Nishihara

Shinji Taniguchi

Jun Tsutsumi

Masafumi Iwaki

Toshio Nishizawa

Go Endo

A radio frequency ladder filter comprises a plurality of series bulk acoustic wave (BAW) resonators electrically connected in series between an input and an output, a plurality of shunt BAW resonators electrically connected between nodes between adjacent ones of the plurality of series BAW resonators and ground, and at least one parallel BAW resonator electrically connected in parallel with one of the plurality of series BAW resonators to increase attenuation in a lower side of a stop band of the radio frequency ladder filter.

Ladder filter including additional resonator for higher attenuation

A ladder type acoustic wave filter is disclosed. The acoustic wave filter can include a plurality of parallel arm resonators and a plurality of series arm resonators, in which an electromechanical coupling coefficient of a parallel arm resonator closest to an input node of the acoustic wave filter among the plurality of parallel arm resonators can be smaller than an electromechanical coupling coefficient of a series arm resonator closest to the input node among the plurality of series arm resonators.

Bulk acoustic wave filters for improving noise factor

A surface acoustic wave resonator comprises at least one set of interdigital transducer (IDT) electrodes disposed on an upper surface of a piezoelectric substrate between first and second reflector gratings, a layer of silicon nitride disposed over the at least one set of IDT electrodes and the first and second reflector gratings, and a continuous trench formed in the layer of silicon nitride over portions of bus bar electrodes and tips of electrode fingers of the at least one set of IDT electrodes and over portions of bus bar electrodes and electrode fingers of the first and second reflector gratings to reduce acoustic leakage at electrode fingers of the first and second reflector gratings proximate the at least one set of IDT electrodes.

Low loss temperature compensated surface acoustic wave filter and duplexer

A surface acoustic wave element includes: a first input wire; a first IDT connected to the first input wire; a second input wire; a second IDT connected to the second input wire; an output wire; and a third IDT connected to the output wire and installed between the first IDT and the second IDT, wherein the first input wire, the second input wire and the output wire are adjacent to each other and withdrawn in a same direction, and a capacitance pattern for applying capacitance is connected at least either between the first IDT and the third IDT or between the second IDT and the third IDT.

Surface acoustic wave element

A duplexer includes a substrate including an insulation layer, an upper interconnection layer provided on an upper surface of the insulation layer, a lower interconnection layer provided on a lower surface of the insulation layer, and an inner interconnection layer provided in the insulation layer, the inner interconnection layer including an inner ground pad, at least one acoustic wave filter chip mounted on an upper surface of the substrate, signal pads provided on the upper interconnection layer and connected to signal electrodes of the at least one acoustic wave filter chip, and an upper ground pad that is provided in the upper interconnection layer so as to be located between the signal pads and is connected to a ground electrode of the at least one acoustic wave filter, wherein DDand DTwhere Dis a minimum distance between the signal pads and the upper ground pad, Dis a minimum distance between the signal pads and the inner ground pad, and Tis a thickness of the insulation layer between the upper interconnection layer and the inner interconnection layer.

Duplexer having specified relationship of the minimum distances between signal pads and specific ground pads

An antenna duplexer is provided, which can be built with a smaller size and lower height than ever without compromising out-of-band attenuation characteristic and isolation characteristic between a transmit terminal and a receive terminal. The antenna duplexer includes a transmit filter provided between an antenna terminal and the transmit terminal, and a receive filter provided between the antenna terminal and the receive terminal. The filters are enclosed by a package, in which a ground pattern for the receive filter is separated from other ground patterns.

Antenna duplexer

A surface acoustic wave device having a surface acoustic wave filter having a comb-shaped electrode pattern formed on a piezoelectric element, electrode terminals for inputting and outputting of the surface acoustic wave filter are connected with corresponding electrode patterns of a package through bumps, wherein the comb-shaped electrode pattern has a pair of reflective electrodes, and an input comb-shaped electrode and an output comb-shaped electrode disposed between the pair of reflective electrodes; and an electrode terminal of either the input comb-shaped electrode or an output comb-shaped electrode is disposed such that the electrode terminal is positioned on the side opposite to the side of the other electrode terminal sandwiching a grounded electrode using a routing pattern.

Growing community of inventors

Yokohama, Japan

Koichi Hatano