Abstract: An elastic wave filter has an unbalanced signal terminal, first and second balanced signal terminals, and first through fifth IDT electrodes arranged in ordinal order between a pair of grating reflectors. Wiring electrodes of the third and fifth IDT electrodes are disposed adjacent a ground electrode of the fourth IDT electrode, wiring electrodes of the second and third IDT electrodes are disposed adjacent one another, and ground electrodes of the first and second IDT electrodes are disposed adjacent one another. The unbalanced signal terminal is connected to the wiring electrodes of the first, third, and fifth IDT electrodes, and the first and second balanced signal terminals are connected to the wiring electrodes of the second and fourth IDT electrodes, respectively.

Abstract: A duplexer includes: a transmit filter connected between a transmit terminal and an antenna terminal and including series resonators and parallel resonators connected in a ladder form; and a receive filter connected between a receive terminal and the antenna terminal, wherein at least one of resonators, which are resonators other than a first series resonator and a first parallel resonator located at a first stage as viewed from a side of the transmit terminal and a second series resonator and a second parallel resonator located at a first stage as viewed from a side of the antenna terminal and have electrostatic capacitances less than an electrostatic capacitance of at least one of the first series resonator, the first parallel resonator, the second series resonator, and the second parallel resonator in the series resonators and the parallel resonators, is divided in series.

Abstract: An elastic wave filter device includes serial and parallel arms and a plurality of elastic wave resonators. Each elastic wave resonator includes an IDT electrode. In the case where a direction in which electrode fingers extend is taken as a width direction of the IDT electrode, the IDT electrode includes a central area at a center in the width direction, a low acoustic velocity area at an outer side portion of the central area, and a high velocity area at a farther outer side portion thereof. A width of the low acoustic velocity area of at least one elastic wave resonator differs from a width of the low acoustic velocity area of the other elastic wave resonators.

Abstract: A surface acoustic wave device includes: comb electrodes that are provided on a piezoelectric substrate, respectively has a plurality of electrode fingers, a plurality of dummy electrode fingers and a bus bar, edges of the electrode fingers of one of the comb electrodes facing the dummy electrode fingers of the other; and an added film that is provided at least under the bus bar of the comb electrodes and under the electrode fingers and the dummy electrode fingers in a first region and is not provided in a crossing region where the electrode fingers of the one of the comb electrodes and the electrode fingers of the other cross each other, the first region being a region between front edges of the dummy electrodes and edges of the dummy electrodes connected to the bus bar and extending in an alignment direction of the electrode fingers.

Abstract: Provided is a high frequency module capable of reducing size and cost. A high frequency module includes an LC filter having an inductor formed through a thin film process and a capacitor also formed through a thin film process, and a piezoelectric resonator that is connected in series to the LC filter and serves as a trap filter having a resonant frequency at the outside of a passing band of the LC filter.

Abstract: A filter device includes a piezoelectric substrate, an IDT arranged on a major surface of the piezoelectric substrate to define a surface acoustic wave resonator, a wiring electrode that is electrically connected to the IDT, and an acoustic member located on a major surface of the piezoelectric substrate near or adjacent to the IDT and that has an acoustic impedance different from that of the piezoelectric substrate. The wiring electrode that is to be disposed in the vicinity of the IDT is located on the acoustic member.

Abstract: A reactance filter can be use branching technology. A series circuit contains a first filter element, a second filter element and a third filter element. Each filter element includes a first impedance element that is connected in series with an impedance element of an adjacent element. Each filter element also includes a second element connected to the first impedance element of that filter. The first and/or second impedance element of each filter element comprises a includes a resonator. Each impedance element has a bandwidth that is expressed by its pole zero distance and each filter element comprises a means for setting the bandwidths of the impedance elements.

Abstract: A SAW filter in which a plurality of IDT electrodes is disposed in the propagation direction of a SAW and ground terminals are separated. The present invention has an advantage in that the attenuation effect of the SAW filter is improved. Furthermore, a skirt characteristic on the high frequency side of a transmission stage and a skirt characteristic on the low frequency side of a reception stage can be improved. Furthermore, an equivalent pass band characteristic can be achieved and a skirt characteristic on the high frequency side and a skirt characteristic on the low frequency side can be improved. Furthermore, the number of bridge electrodes can be reduced and thus a process can be simplified because ground terminals are separated.

Abstract: An elastic wave filter includes a transmission circuit provided on a first main surface of a first piezoelectric substrate and a reception circuit provided on a second main surface of a second piezoelectric substrate. A mounting board on which the elastic wave filter is mounted includes a first ground electrode opposed to the transmission circuit; a first rear surface ground electrode overlapped with the transmission circuit in plan view of a rear surface; a second ground electrode opposed to the reception circuit; a second rear surface ground electrode overlapped with the reception circuit in plan view of the rear surface; a line electrode used for connection between the first ground electrode and the second ground electrode; and a first via electrode and a second via electrode passing through the mounting board. An amount of heat transfer per unit time of the second via electrode is greater than an amount of heat transfer per unit time of the first via electrode.

Abstract: A solid mount bulk acoustic wave resonator, comprises a first electrode; a second electrode; a piezoelectric layer disposed between the first and second electrodes; and an acoustic reflector comprising a plurality of layers and disposed beneath the first electrode, the second electrode and the piezoelectric layer. An overlap of the acoustic reflector, the first electrode, the second electrode and the piezoelectric layer defines an active area of the acoustic resonator, and the piezoelectric layer extends over an edge of the first electrode. The acoustic resonator also comprises a bridge adjacent to a termination of the active area of the acoustic resonator. The bridge overlaps a portion of the first electrode.

Abstract: A surface acoustic wave filter includes a longitudinally coupled resonator first filter section and a longitudinally coupled resonator second filter section that is electrically connected to the first filter section in parallel or in series and that is provided next to the first filter section in a surface acoustic wave propagation direction. The first filter section includes a first interdigital transducer group arranged in the surface acoustic wave propagation direction. The second filter section includes a second interdigital transducer group arranged in the surface acoustic wave propagation direction. A reflector between the first interdigital transducer group and the second interdigital transducer group is an integrated shared reflector. A number of electrode fingers in reflecting units in the shared reflector is an odd number of no less than nine.

Abstract: An acoustic wave device includes: a first chip that includes a first substrate, and a first filter formed on a first surface of the first substrate; and a second chip that includes a second substrate, and a second filter formed on a second surface of the second substrate, the second surface being located in a plane different from the first surface.

Abstract: The present invention relates to a capacitor for a SAW filter, the SAW filter, and a method of manufacturing thereof, and more specifically, to a capacitor for a SAW filter including a first metal layer formed on a substrate; an insulation layer formed on the first metal layer; and a second metal layer formed on the insulation layer and overlapped with partially or totally of the first metal layer, in which the insulation layer is formed to be extended to the top of an IDT formed on the substrate, the SAW filter on which such a capacitor for a SAW filter is mounted, and a method of manufacturing thereof.

Abstract: In an electronic component, a functional circuit, signal wiring electrically connected to the functional circuit, and ground wiring electrically connected to the functional circuit and electrically connected to a ground potential are located on one surface of a circuit substrate, a frame member is provided to secure a region between itself and an outer peripheral edge of a first main surface of the circuit substrate and so as to surround the functional circuit, the ground wiring extends from inside to outside the frame member, and a shield member extends from a second main surface of the circuit substrate to a region on the first main surface via the side surfaces, the shield member being electrically connected to the ground wiring in the region outside the frame member.

Abstract: In an elastic wave filter device, a package substrate is provided with an elastic wave filter chip defining a ladder circuit including a plurality of series arm resonators and a plurality of parallel arm resonators, and a first inductance connected in parallel with at least one of the series arm resonators and a second inductance connected between at least one of the parallel arm resonators and a ground potential. The first inductance and the second inductance provided in the package substrate, and the first inductance is magnetically coupled to the second inductance to shift a frequency position of an attenuation pole.

Abstract: A filter includes a plurality of resonance cavities, where a resonance tube and a tuning bolt penetrating into space enclosed by the resonance tube are disposed in each resonance cavity; further includes a tuning part disposed between the tuning bolt and the resonance tube, where the tuning part and the resonance tube form a first capacitor, and the tuning part and the tuning bolt form a second capacitor; and further includes an adjusting structure used for rotating the tuning part, so as to change relative areas between the tuning part and the resonance tube and between the tuning part and the tuning bolt, so that the first capacitor and the second capacitor change synchronously. In the present invention, the tuning part is disposed between the tuning bolt and the resonance tube, so that the tuning part forms a double-capacitor structure with the resonance tube and the tuning bolt.

Abstract: A filter working with surface acoustic waves comprises a piezoelectric substrate (SU), a first transducer (IDT1) arranged in the acoustic track coupled to an input, having a first mean finger period (pi) assigned to a center frequency of a pass band of the filter and a second transducer (IDT2) arranged in the acoustic track coupled to an output, having the same first mean finger period (p1), and a reflector arranged between first and second transducer having a second mean finger period (p2) assigned to a stop band frequency different from the center frequency. Further, a new type of very broad bandwidth filters with small insertion loss and high return loss and high rejection are given that use a substrate that can propagate a PSAW and comprises fan shaped transducers.

Abstract: An elastic wave resonator including comb-shaped electrodes and reflector electrodes formed on a piezoelectric substrate. In one example, an overlapping portion between the comb-shaped electrodes includes a first overlapping region and second overlapping regions. The second overlapping regions can be provided on both outside edges of the first overlapping region. In one example, the overlapping width of the first overlapping region is greater than the overlapping width of the second overlapping region, and the electrode finger pitch in the second overlapping region is greater than the electrode finger pitch in the first overlapping region.

Abstract: An elastic wave filter including a substrate, a signal line disposed on the substrate and connecting a first signal terminal to a second signal terminal, a plurality of series resonators connected to the signal line in series, and a plurality of parallel resonators connected to the signal line. At least one of the series resonator having an anti-resonant frequency closest to the passband of the filter among the plurality of series resonators, and/or the parallel resonator having a resonant frequency closest to the passband of the filter among the plurality of parallel resonators, is covered with a dielectric film that is relatively thicker than a dielectric film covering the other series and/or parallel resonators.

Abstract: An acoustic wave device includes: a piezoelectric substrate; and an IDT formed on the piezoelectric substrate, wherein an anisotropy coefficient is positive, an overlap region where electrode fingers of the IDT overlap each other includes a center region and an edge region, the electrode fingers in the center and edge regions are continuously formed, the electrode finger in the edge region is inclined with respect to the electrode finger in the center region so that a pitch in a width direction of the electrode finger in the edge region is greater than a pitch in a width direction of the electrode finger in the center region, and an angle between the width direction in the center region and a crystal axis orientation of the piezoelectric substrate is less than an angle between the width direction in the edge region and the crystal axis orientation.