Patent
Surface acoustic wave filter
TLDR
In this paper, the SAW filter comprises a series resonator group including a plurality of surface acoustic wave electrodes formed on a surface of a piezoelectric substrate and electrically disposed in series between an input terminal and an output terminal.Abstract:
A surface acoustic wave filter employing surface acoustic wave electrodes for forming a ladder filter circuit according to the invention, the SAW filter comprises a series resonator group including a plurality of surface acoustic wave electrodes formed on a surface of a piezoelectric substrate and electrically disposed in series between an input terminal and an output terminal; and a parallel resonator group including a plurality of surface acoustic wave electrodes individually electrically disposed in parallel between an input- or output-terminal of the individual surface acoustic wave electrodes of the series resonator group and a ground electrode, wherein a part number of the surface acoustic electrodes of the parallel resonator group is configured to deteriorate an obtained Q value and presents a resonant frequency which is lower than an antiresonant frequency and higher than a resonant frequency respectively formed by the other surface acoustic wave electrodes of the parallel resonator group Thus is obtained a steep shoulder characteristic curve on a lower side of a passbandread more
Citations
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References
More filters
Patent
Surface acoustic wave filter
TL;DR: In this paper, a half-cut groove is made between a 1st coupling surface acoustic wave element 3 and a 2nd lateral coupling surface acoustic wave element 4 to prevent interference between both the lateral coupling surfaces acoustic wave elements 3, 4, and the arrangement of wire bonding pads required for wire bonding pad for bridging over the halfcut groove.
Patent
Surface acoustic wave filter
TL;DR: In this article, a ladder-type SAW filter was proposed to provide an element having arbitrary band width and having sharp shoulder characteristics by connecting plural resonators which are composed of IDT electrodes coated with protecting films, on a piezoelectric substrate to a ladder type circuit and preparing the protecting films on the respective resonators more than two kinds of materials and/or making the thickness of protecting films different at two spots at least.
Patent
Surface acoustic wave filter
TL;DR: In this article, the authors proposed a method to eliminate the occupation area of a resistance on a printed board and to absorb an unnecessary surface acoustic wave by printing and forming the resistance to be connected to a grid electrode couple for exciting or receiving an acoustic wave on the piezoelectric substrate.
Patent
Surface acoustic wave filter
TL;DR: In this paper, an intermediate bus bar 5 is arranged between bus bars 3, 4 which are relatively arranged in parallel and a first and a second comb-line electrodes 6, 7 are constituted by each bus bar and the intermediate bus bars by the surface acoustic wave filter.
Patent
Surface acoustic wave filter
TL;DR: In this article, a surface acoustic wave filter to be disclosed comprises a plurality of series-arm resonators in which a first series arm resonator connected to an input terminal, a second series arm resonance connecting to an output terminal, and a third arm resonance connected between the first and second series arms resonators, respectively connected in series.