US 11,916,530 B2
Acoustic-wave-based filter for wideband applications
Georgiy Sevskiy, Munich (DE); Mykola Shevelov, Munich (DE); Bohdan Bravichev, Munich (DE); Mathieu Pijolat, Grenoble (FR); Stefan Freisleben, Neubiberg (DE); and Patric Heide, Vaterstetten (DE)
Assigned to RF360 Singapore Pte. Ltd., Singapore (SG)
Filed by RF360 SINGAPORE PTE. LTD., Singapore (SG)
Filed on Dec. 6, 2021, as Appl. No. 17/457,720.
Prior Publication US 2023/0179168 A1, Jun. 8, 2023
Int. Cl. H03H 9/02 (2006.01); H03H 9/00 (2006.01); H03H 9/05 (2006.01); H03H 9/125 (2006.01)
CPC H03H 9/02007 (2013.01) [H03H 9/0014 (2013.01); H03H 9/0504 (2013.01); H03H 9/125 (2013.01)] 26 Claims
OG exemplary drawing
 
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.