US 12,375,055 B2
Filter device and radio frequency front-end circuit including the same
Makoto Ogata, Nagaokakyo (JP); and Keisuke Ogawa, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Oct. 21, 2022, as Appl. No. 17/970,650.
Application 17/970,650 is a continuation of application No. PCT/JP2021/025591, filed on Jul. 7, 2021.
Claims priority of application No. 2020-123702 (JP), filed on Jul. 20, 2020; application No. 2020-142400 (JP), filed on Aug. 26, 2020; and application No. 2021-038540 (JP), filed on Mar. 10, 2021.
Prior Publication US 2023/0044655 A1, Feb. 9, 2023
Int. Cl. H03H 7/01 (2006.01); H01F 27/28 (2006.01); H01G 4/30 (2006.01)
CPC H03H 7/0115 (2013.01) [H01F 27/2804 (2013.01); H01G 4/30 (2013.01); H01F 2027/2809 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A filter device, comprising:
an input terminal;
an output terminal;
a main body;
a common electrode on the main body;
a ground terminal; and
a first LC parallel resonator, a second LC parallel resonator, and a third LC parallel resonator; wherein
each of the first LC parallel resonator, the second LC parallel resonator, and the third LC parallel resonator is connected to the common electrode and the ground terminal;
each of the first LC parallel resonator, the second LC parallel resonator, and the third LC parallel resonator includes:
a capacitor;
a first via including one end connected to the common electrode and another end connected to the ground terminal through the capacitor; and
a second via including one end connected to the common electrode and another end connected to the ground terminal without through the capacitor; and
the second via is connected between portions of the common electrode to which first vias of two adjacent LC parallel resonators of the first, second, and third LC parallel resonators are connected, each of the first vias being the first via including the one end connected to the common electrode and the other end connected to the ground terminal through the capacitor.