US 12,289,096 B2
Acoustic wave filter device
Yuta Takeuchi, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Feb. 4, 2022, as Appl. No. 17/592,584.
Application 17/592,584 is a continuation of application No. PCT/JP2020/027908, filed on Jul. 17, 2020.
Claims priority of application No. 2019-144407 (JP), filed on Aug. 6, 2019.
Prior Publication US 2022/0158623 A1, May 19, 2022
Int. Cl. H03H 9/56 (2006.01); H03H 9/13 (2006.01); H03H 9/17 (2006.01)
CPC H03H 9/568 (2013.01) [H03H 9/13 (2013.01); H03H 9/17 (2013.01)] 16 Claims
OG exemplary drawing
 
1. An acoustic wave filter device comprising:
a first signal terminal;
a second signal terminal;
a series arm circuit connected between the first signal terminal and the second signal terminal and including a plurality of series arm resonators; and
a parallel arm circuit connected in series between the series arm circuit and a ground potential and including at least one parallel arm resonator; wherein
the plurality of series arm resonators include a first series arm resonator and a second series arm resonator having different anti-resonant frequencies from each other;
the anti-resonant frequency of the first series arm resonator is lowest among anti-resonant frequencies of the plurality of series arm resonators; and
the first series arm resonator and the second series arm resonator are connected to each other without another circuit element interposed therebetween.