CPC H03H 9/02007 (2013.01) [H03H 9/0014 (2013.01); H03H 9/0504 (2013.01); H03H 9/125 (2013.01)] | 26 Claims |
1. A filter circuit comprising:
a first filter stage comprising:
a first acoustic wave resonator coupled in a series path between a first port of the filter circuit and a second port of the filter circuit;
a first inductor-capacitor (LC) tank circuit;
a first capacitor coupled between a first terminal of the first acoustic wave resonator and the first LC tank circuit, the first LC tank circuit being coupled between the first capacitor and a reference potential node;
a second capacitor coupled between a second terminal of the first acoustic wave resonator and the first LC tank circuit; and
an inductive element coupled between the first LC tank circuit and the reference potential node; and
one or more other filter stages coupled to the first filter stage.
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