THERMO-STABLE FILTER ON SURFACE ACOUSTIC WAVES Russian patent published in 2006 - IPC H03H3/08 H03H9/64 

FIELD: acoustical electronics, possible use for development and manufacture of narrowband filters on surface acoustic waves with low temperature coefficient of frequency.

SUBSTANCE: thermo-stable filter on surface acoustic wave contains piezo-electric substrate with oppositely-rod transformers formed on the surface and with bimetallic plate fastened to back side of piezo-electric substrate. Bimetallic plate has rigid holder in the center of piezo-electric substrate, while on the ends frequency bimetallic plate spring elements are rigidly held, which are freely pressed to ends of piezoelectric substrate with force, forming preliminary bend of piezoelectric substrate at environment temperature 20-25° and resulting in increase of original central frequency of surface acoustic wave filter for 2-4 kHz.

EFFECT: increased temperature stability of narrowband devices on surface acoustic waves and decreased deviation of central frequency when environment temperature changes.

5 dwg