Design and layout method of piezoelectric acoustic wave filter

Abstract

The invention discloses a design and layout method of a piezoelectric acoustic wave filter. The filter comprises multiple series stages connected in series and parallel stages positioned between every two adjacent series stages, wherein each series stage comprises at least one resonator; each parallel stage comprises at least one resonator; distributed capacitance is formed between the resonator in one series stage and the resonator in another none-adjacent series stage, and the distributed capacitance between the resonator in the series stage and the resonator in one none-adjacent series stage with higher series difference is less than that between the resonator in the series stage and the resonator in one none-adjacent series stage with lower series difference. According to the design and layout method, relative magnitude of distributed capacitances between resonators in different series stages can be determined according to the series difference between the series stages of the piezoelectric acoustic wave filter, so that the layout of the resonators of the piezoelectric acoustic wave filter can be reasonably designed, the electric isolation degree of the piezoelectric acoustic wave filter can be enhanced and further the filtering inhibition performance of the piezoelectric acoustic wave filter can be improved.

Description

technical field [0001] The present invention relates to the field of filters, and in particular, to a design and layout method of a piezoelectric acoustic wave filter. Background technique [0002] With the rapid popularization of wireless communication equipment and the continuous expansion of user needs, handheld mobile communication products are developing towards miniaturization and portability. With the continuous reduction of product size, product prices continue to decline, but the demand for functions But gradually strengthened. Generally, in handheld mobile communication products, discrete passive devices often occupy a larger space than active circuits based on CMOS and GaAs processes. In the development wave of miniaturization, the filter as a representative of passive components plays an extremely important role. It is necessary to further reduce the size of the filter while maintaining or even improving the performance of the filter. [0003] In today's handh...

AI Technical Summary

Problems solved by technology

[0009] In view of the unreasonable layout of the resonator in the piezoelectric acoustic wave filter in the related art, which leads to the low electrical isolation of the piezoelectric acoustic wave filter, thereby affecting its suppression filtering performance, the present invention proposes a piezoelectric acoustic wave The design and layout method of the filter can reasonably design the layout layout of the resonator in the piezoelectric acoustic wave filter, and enhance the electrical isolation of the piezoelectric acoustic wave filter, thereby improving its suppression filtering performance

Images