Title:
ELASTIC-WAVE FILTER DEVICE
Document Type and Number:
WIPO Patent Application WO/2021/024762
Kind Code:
A1
Abstract:
Provided is an elastic wave filter device capable of improving steepness, and increasing the amount of attenuation outside a passband in a broad frequency range near the passband. The elastic wave filter device 1 comprises: a first signal terminal A1; a second signal terminal A2; a series arm circuit A including a plurality of series arm resonators, connected between the first signal terminal A1 and the second signal terminal A2; and a parallel arm circuit including at least one parallel resonator, connected in series between the series arm circuit A and the ground potential. The plurality of series arm resonators include a first series arm resonator S16 and a second series arm resonator S17 that have different antiresonance frequencies. The antiresonance frequency of the first series arm resonator S16 is the lowest among the antiresonance frequencies of the plurality of series arm resonators. The first series arm resonator S16 and the second series arm resonator S17 are connected to each other with no other circuit element therebetween.
Inventors:
TAKEUCHI YUTA (JP)
Application Number:
PCT/JP2020/027908
Publication Date:
February 11, 2021
Filing Date:
July 17, 2020
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
International Classes:
H03H9/17; H03H9/25; H03H9/54; H03H9/64
Domestic Patent References:
| WO2019138812A1 | 2019-07-18 |
Foreign References:
| JP2018067874A | 2018-04-26 | |||
| JP2007074698A | 2007-03-22 | |||
| JP2016136687A | 2016-07-28 |
Attorney, Agent or Firm:
MIYAZAKI & METSUGI (JP)
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