US 11,811,381 B2
Filter element
Satoshi Shigematsu, Nagaokakyo (JP); and Kenichi Ishizuka, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Jun. 24, 2021, as Appl. No. 17/356,571.
Application 17/356,571 is a continuation of application No. PCT/JP2020/031308, filed on Aug. 19, 2020.
Claims priority of application No. 2019-162553 (JP), filed on Sep. 6, 2019.
Prior Publication US 2021/0320638 A1, Oct. 14, 2021
Int. Cl. H03H 7/01 (2006.01); H03H 7/09 (2006.01); H01F 27/28 (2006.01); H01F 27/29 (2006.01); H01F 27/40 (2006.01); H01G 4/012 (2006.01); H01G 4/30 (2006.01)
CPC H03H 7/0115 (2013.01) [H01F 27/2804 (2013.01); H01F 27/29 (2013.01); H01F 27/40 (2013.01); H01G 4/012 (2013.01); H01G 4/30 (2013.01); H03H 7/09 (2013.01); H01F 2027/2809 (2013.01)] 10 Claims
OG exemplary drawing
 
2. A filter element comprising:
a multilayer body including laminated base material layers, internal elements in the multilayer body, a first terminal electrode, a second terminal electrode, and a reference potential electrode on an outer surface of the multilayer body; wherein
the internal elements include a first coil, a second coil, a first capacitor, and a second capacitor;
the first coil and the second coil have winding axes in a laminated direction of the base material layers and a coil opening of the first coil is overlapped with a coil opening of the second coil for magnetic coupling;
the first capacitor and the second capacitor are on base material layers of the multilayer body different from base material layers on which the first coil and the second coil are provided;
the first coil is differentially connected to the second coil;
the second capacitor is connected in parallel to a series circuit of the first coil and the second coil;
the first capacitor is connected between a position where the first coil is connected to the second coil and the reference potential electrode;
mutual inductance caused by coupling between the first coil and the second coil and the first capacitor provides a first attenuation pole; and
a parallel connection circuit of the series circuit and the second capacitor provides a second attenuation pole.