Surface acoustic wave resonator
AssigneesHitachi, Ltd., Hitachi Denshi Kabushiki
InventorsMitsutaka Hikita, Atsushi Sumioka, Yoshikatu Ishida
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AssigneesHitachi, Ltd., Hitachi Denshi Kabushiki
InventorsMitsutaka Hikita, Atsushi Sumioka, Yoshikatu Ishida
Estimating the term…
In order to realize an SAW filter withstanding high power, a plurality of single open-ended surface acoustic wave resonators are connected in series, and an earth conductor is disposed at least on a part of rear face of a piezoelectric substrate constituting the surface acoustic wave resonators. And static capacities formed between said earth conductor and electrode conductors on the piezoelectric substrate constituting the surface acoustic wave resonators are utilized as constituents of the filter circuit. In the above described structure, a part of input power is not converted into acoustic energy, but directly transmitted to the output side. Since the mechanical stress imposed upon the electrode material and the piezoelectric substrate is thus lightened, the SAW filter can withstand a large power signal.
A surface acoustic wave filter comprising:
Dependencies are inferred from the claim text.