| CPC H03H 9/568 (2013.01) [H03H 9/02015 (2013.01); H03H 9/02031 (2013.01); H03H 9/02062 (2013.01); H03H 9/02228 (2013.01); H03H 9/132 (2013.01); H03H 9/174 (2013.01); H03H 9/176 (2013.01); H03H 9/562 (2013.01); H03H 9/564 (2013.01); H03H 3/02 (2013.01); H03H 2003/023 (2013.01); H03H 9/02039 (2013.01); H10N 30/877 (2023.02)] | 18 Claims |

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1. A filter device, comprising:
a plurality of resonators connected in a ladder filter circuit, each resonator of the plurality of resonators comprising an interdigital transducer (IDT) with interleaved fingers disposed on a respective piezoelectric diaphragm;
a first frequency setting dielectric layer having a first thickness disposed over and between the interleaved fingers of one or more IDTs of a first subset of the plurality of resonators; and
a second frequency setting dielectric layer having a second thickness greater than the first thickness disposed over and between the interleaved fingers of one or more IDTs of a second subset of the plurality of resonators, wherein the first subset and the second subset are not identical,
wherein each piezoelectric diaphragm and each IDT of the plurality of resonators are configured such that a respective radio frequency signal applied to the IDT excites a respective primary shear acoustic mode within the respective piezoelectric diaphragm.
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