ACOUSTIC WAVE FILTER WITH WIDE BANDWIDTH OF ATTENUATION REGION

• Main Author: Iwaki, Masafumi
• Format: Patent
• Language: English
• Published: 10.08.2023
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS

An acoustic wave filter provided herein comprises a plurality of series resonators, and a plurality of shunt resonators disposed between the series resonators and a ground, at least one shunt resonator including a substrate, a pair of IDT electrodes disposed on the substrate, each of the IDT electrodes including a bus bar and a plurality of fingers extending from the bus bar, the plurality of fingers of the pair of IDT electrodes including a first group of fingers located at a center region of the pair of IDT electrodes and a second group of fingers located at edge regions on both sides of the center region, the first group of fingers having an average pitch distance shorter than an average pitch distance of the second group of fingers to improve a response at a rejection band of the acoustic wave filter.