A surface acoustic wave bandpass filter, a design method thereof and an electronic device

Abstract

The application discloses a surface acoustic wave band-pass filter and a design method and an electronic device thereof, wherein the method comprises the following steps: determining a first structure parameter of a resonator and determining a second structure parameter, the second structure parameter comprising piezoelectric material and thickness of a piezoelectric film; extracting a first relationship and a second relationship related to an in-plane transmission direction of each resonator; based on the first relationship and the second relationship, building a target filter; the target filter comprises a basic resonator group and a compensation resonator group, the frequency temperature coefficient of the basic resonator group at the center frequency of the filter is zero, and the frequency temperature coefficient of the compensation resonator group at the transmission zero point is zero; if the frequency temperature coefficient of the target filter is not zero, returning to the step of determining the second structure parameter until the frequency temperature coefficient of the target filter is zero. The application ensures that the passband range of the filter does not change with temperature by allowing the resonators to interact, and realizes the band-pass filter with a frequency temperature coefficient of zero.

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