US 11,838,043 B2
Filter circuit module, filter circuit element, filter circuit, and communication apparatus
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 Jul. 9, 2021, as Appl. No. 17/371,185.
Application 17/371,185 is a continuation of application No. PCT/JP2020/002322, filed on Jan. 23, 2020.
Claims priority of application No. 2019-030410 (JP), filed on Feb. 22, 2019.
Prior Publication US 2021/0336648 A1, Oct. 28, 2021
Int. Cl. H04B 1/10 (2006.01); H04B 1/40 (2015.01); H03H 7/03 (2006.01); H03H 7/09 (2006.01)
CPC H04B 1/40 (2013.01) [H03H 7/03 (2013.01); H03H 7/09 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A filter circuit module comprising:
a filter circuit element including a multilayer body including a plurality of base material layers including a base material layer with a conductive pattern provided thereon, a circuit board including the filter circuit element mounted thereon, and a first inductor; wherein
the filter circuit element includes a resonant circuit capacitor defining a portion of an LC parallel resonant circuit, and a phase-shift circuit;
the circuit board includes a second inductor;
the phase-shift circuit includes a primary coil, a secondary coil, and a capacitor-between-input-and-output, the primary coil being magnetically coupled to the secondary coil;
the LC parallel resonant circuit includes the second inductor and the resonant circuit capacitor connected in parallel to the second inductor;
the capacitor-between-input-and-output is connected between a first end of the primary coil and a first end of the secondary coil;
the first end of the primary coil is connected to the first inductor;
a second end of the primary coil is connected to a second end of the secondary coil;
a first end of the resonant circuit capacitor is connected to the first end of the secondary coil;
a second end of the resonant circuit capacitor is connected to the second end of the secondary coil;
the second inductor is provided in the circuit board;
the primary coil and the secondary coil are overlapped with the second inductor, viewed in a laminated direction of the multilayer body;
the resonant circuit capacitor is closer to a mounting surface on which the filter circuit element is mounted on the circuit board, compared with the primary coil and the secondary coil; and
the resonant circuit capacitor includes a plurality of capacitor electrodes, and the plurality of capacitor electrodes include a capacitor electrode covering a coil opening of the primary coil and a coil opening of the secondary coil, viewed in the laminated direction.