US 11,838,003 B2
Composite filter device
Junpei Yasuda, Nagaokakyo (JP); and Morio Takeuchi, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Jun. 9, 2022, as Appl. No. 17/836,094.
Application 17/836,094 is a continuation of application No. 16/551,771, filed on Aug. 27, 2019, granted, now 11,387,803.
Application 16/551,771 is a continuation of application No. PCT/JP2018/009476, filed on Mar. 12, 2018.
Claims priority of application No. 2017-070565 (JP), filed on Mar. 31, 2017.
Prior Publication US 2022/0302893 A1, Sep. 22, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. H03H 9/02 (2006.01); H03H 7/075 (2006.01); H03H 7/38 (2006.01); H03H 7/46 (2006.01); H03H 9/64 (2006.01); H03H 9/72 (2006.01)
CPC H03H 9/0222 (2013.01) [H03H 7/075 (2013.01); H03H 7/38 (2013.01); H03H 7/46 (2013.01); H03H 9/6483 (2013.01); H03H 9/72 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A composite filter device, comprising:
bandpass filters each including respective one ends and another ends; wherein
the one ends of the bandpass filters are electrically connected in common;
at least one of the bandpass filters includes a first filter electrically connected to the one end, a second filter electrically connected between the first filter and the another end, and a switch electrically connected between the first filter and the second filter; and
complex impedances of the first filter and the second filter have a same polarity in a pass band of another one of the bandpass filters different from the at least one of the bandpass filters when viewed from a same point in a circuit between the first filter and the second filter.