Patent ID: 11929737
Assignee: MURATA MANUFACTURING CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A band pass acoustic wave filter having a pass band and an attenuation band on at least one of a lower-frequency side and a higher-frequency side than the pass band, the acoustic wave filter comprising:
a first input/output terminal and a second input/output terminal;
at least one serial arm resonance circuit on a path connecting the first input/output terminal and the second input/output terminal; and
at least one parallel arm resonance circuit between a node on the path and a ground; wherein
each of the at least one serial arm resonance circuit and the at least one parallel arm resonance circuit includes at least one acoustic wave resonator;
a first parallel arm resonance circuit of the at least one parallel arm resonance circuit includes a bridging capacitor connected in parallel to the at least one acoustic wave resonator;
an anti-resonant frequency of the first parallel arm resonance circuit is on the higher-frequency side than the pass band; and
a resonant frequency of a first serial arm resonance circuit of the at least one serial arm resonance circuit is on a lower-frequency side than the anti-resonant frequency of the first parallel arm resonance circuit.