Acoustic wave device and multiplexer
AssigneeMurata Manufacturing Co., Ltd.
InventorKenta MAEDA
Life of this patent
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Abstract
A filter includes multiple acoustic wave resonant circuits. Among the multiple acoustic wave resonant circuits, an acoustic wave resonant circuit includes series-arm resonators connected in series with one another. Each of the series-arm resonators includes an IDT electrode on a piezoelectric substrate, and multiple electrode fingers parallel or substantially parallel to one another. The IDT electrode included in each of the acoustic wave resonators is divided into multiple electrode-finger regions including different duties and defined as a region where two or more electrode fingers including an equal duty are consecutively arranged. When the multiple electrode-finger regions are compared, an electrode-finger pitch, which is an interval between adjacent electrode fingers, decreases as a duty increases.
Claims20
An acoustic wave device comprising:
- a plurality of acoustic wave resonant circuits;
- wherein
- among the plurality of acoustic wave resonant circuits, a first acoustic wave resonant circuit includes a plurality of acoustic wave resonators connected in series with one another;
- each of the plurality of acoustic wave resonators includes an IDT (InterDigital Transducer) electrode on a substrate including piezoelectric properties, and the IDT electrode includes a plurality of electrode fingers parallel or substantially parallel to one another;
- the IDT electrode included in each of the plurality of acoustic wave resonators is divided into a plurality of electrode-finger regions including different duties, each electrode-finger region being defined as a region where two or more electrode fingers including an equal duty are consecutively arranged;
- and
- when the plurality of electrode-finger regions are compared, an electrode-finger pitch, which is an interval between adjacent electrode fingers, decreases as the duty increases.
Dependencies are inferred from the claim text.