Abstract: A multiplexer includes filters and a common terminal connected to an antenna element by a connection path, a first inductance element being connected between the connection path and a reference terminal. A terminal closer to the antenna element among an input terminal and an output terminal of one filter among the filters is connected to a parallel resonator and is connected to the common terminal with a second inductance element interposed therebetween. A terminal closer to the antenna element among an input terminal and an output terminal of each of other filters other than the one filter among the filters is connected to the common terminal and a series resonator.

Abstract: An acoustic wave filter device includes a plurality of acoustic wave resonators. Each of the acoustic wave resonators includes a piezoelectric layer and an IDT electrode provided on the piezoelectric layer. On a surface opposite to a surface of the piezoelectric layer on which the IDT electrode is provided, a low-acoustic-velocity film and a substrate made of a semiconductor are stacked. A routing line electrically connected to an antenna terminal is provided on an insulating film provided on the piezoelectric layer.

Abstract: A filter device includes a substrate having piezoelectricity, a first filter including an IDT electrode disposed on the substrate, a terminal electrode disposed on the substrate, a first wiring electrode disposed on the substrate and connecting the first filter and a terminal electrode, and a dielectric film disposed above the substrate to cover the IDT electrode. At least a portion of the first wiring electrode is not covered with the dielectric film.

Abstract: A multiplexer includes a first reception-side filter and a second reception-side filter whose passband has frequencies higher than the first reception-side filter. The first reception-side filter includes a series arm resonator provided on a first path, and parallel arm resonators provided on a path electrically connecting the first path and ground. A direction connecting tips of a plurality of electrode fingers included in each resonator crosses an elastic wave propagating direction at a certain angle. The parallel arm resonator closest to a common connection terminal does not include third electrode fingers, and the other parallel arm resonators include third electrode fingers.

Abstract: A multiplexer includes a common connection terminal on a first surface of a substrate and to be connected to an antenna element, and transmission-side and reception-side elastic wave filters of Band25 and Band66 mounted on a second surface of the substrate opposite the first surface, that are connected to the common connection terminal, and that have pass bands different from each other. The transmission-side elastic wave filter of Band66 is located nearest on the substrate to the common connection terminal among the elastic wave filters.

Abstract: A multiplexer includes acoustic wave filters that are electrically connected to a common connection terminal. In a first transmission-side filter of the acoustic wave filters, a series arm resonator closest to the common connection terminal includes acoustic wave resonators that are electrically connected in series and capacitance elements that are electrically connected between at least one of signal paths electrically connecting the acoustic wave resonators to each other and a reference terminal.

Abstract: A quadplexer includes a first filter and a second filter having a pass band frequency that is higher than a pass band frequency of the first filter. The first filter includes series resonators disposed on a first path and parallel resonators disposed on a path that connects the first path and a ground to each other. A direction that connects ends of a plurality of electrode fingers defining each resonator crosses an elastic wave propagation direction at a predetermined angle. The series resonator nearest to a common terminal does not include first electrode fingers, and the other series resonators include the first electrode fingers.

Abstract: A multiplexer includes elastic wave filters with different pass bands, a common terminal to which an inductance element is serially connected in a connection path between an antenna element and the common terminal; and an inductance element. Among the elastic wave filters, a reception input terminal of a first reception filter is connected to the common terminal via the inductance element and is connected to a parallel resonator. Transmission output terminals of transmission filters and a reception input terminal of a second reception filter are connected to the common terminal, are connected to series resonators, and are not connected to parallel resonators.

Abstract: A multiplexer includes filters and a common terminal connected to an antenna element by a connection path, a first inductance element being connected between the connection path and a reference terminal. A terminal closer to the antenna element among an input terminal and an output terminal of one filter among the filters is connected to a parallel resonator and is connected to the common terminal with a second inductance element interposed therebetween. A terminal closer to the antenna element among an input terminal and an output terminal of each of other filters other than the one filter among the filters is connected to the common terminal and a series resonator.

Abstract: A quadplexer includes a filter of a first duplexer that has a passband with frequencies lower than a filter of a second duplexer. A series resonator closest to a common terminal of the filter includes split resonators that are each an elastic wave resonator including an IDT electrode and a reflector, and include first and second split resonators with impedance characteristics having ripples different from each other in a certain frequency range higher than an anti-resonant frequency of the series resonator closest to the common terminal, that is defined by a pitch of electrode fingers included in the reflector, and that is included in a passband of the filter.

Abstract: A multiplexer includes filters on one principal surface of a mounting substrate and having mutually different frequency bands, and an inductance element which is incorporated in the mounting substrate and one end of which is connected to one end of the filter. The other end of the inductance element and one end of each of the filters, are connected to each other at a common connection point. The inductance element is defined by spiral wiring conductors disposed in first and second wiring layers provided in an inner layer of the mounting substrate. The mounting substrate includes third and fourth wiring layers which are adjacent to the first and second wiring layers, and in which no ground pattern is provided in a portion corresponding to a formation region of the inductance element.

Abstract: A multiplexer includes elastic wave filters with different pass bands, a common terminal to which an inductance element is serially connected in a connection path between an antenna element and the common terminal; and an inductance element. Among the elastic wave filters, a reception input terminal of a first reception filter is connected to the common terminal via the inductance element and is connected to a parallel resonator. Transmission output terminals of transmission filters and a reception input terminal of a second reception filter are connected to the common terminal, are connected to series resonators, and are not connected to parallel resonators.

Abstract: A transmission filter includes five series resonators that include functional electrodes provided on a piezoelectric substrate, and connected in series with each other between a transmission input terminal and an antenna terminal, and parallel resonators. Frequency differences between the anti-resonant frequencies and the resonant frequencies of the series resonators other than the series resonator connected so as to be closest to the transmission input terminal and the series resonator connected so as to be closest to the antenna terminal are smaller than frequency differences of the series resonators, and anti-resonant frequencies of the series resonators are lower than the anti-resonant frequencies of the series resonators.

Abstract: An elastic wave filter device includes a piezoelectric film, a high acoustic velocity support substrate in which an acoustic velocity of a propagating bulk wave is larger than an acoustic velocity of a main mode elastic wave propagating in the piezoelectric film, and IDT electrodes in contact with the piezoelectric film. A serial arm resonator and a parallel arm resonator are defined by the IDT electrodes such that, a direction in which tips of first and second electrode fingers are connected defines a tilt angle with respect to a propagation direction of elastic waves excited by the IDT electrodes. A tilt angle of the serial arm resonator is different from a tilt angle of the parallel arm resonator.

Abstract: A filter device includes a longitudinally coupled resonator elastic wave filter that includes IDT electrodes including low acoustic velocity regions in outer side portions of center regions of the IDT electrodes and high acoustic velocity regions in outer side portions of the low acoustic velocity regions in a direction orthogonal or substantially orthogonal to an elastic wave propagation direction, and defines and functions as a first bandpass filter, and elastic wave resonators that are electrically connected to the longitudinally coupled resonator elastic wave filter.

Abstract: A composite multiplexer includes a first multiplexer, a second multiplexer, and a second LC circuit. The first multiplexer includes first band pass filter circuits and first LC circuits connected to end portions of the first band pass filter circuits that are opposite to a first terminal, respectively. The second multiplexer includes second band pass filter circuits. The second LC circuit is connected between the first terminal and the second multiplexer.

Abstract: A filter includes a LiTaO3 piezoelectric layer having a cut angle, a high acoustic velocity support substrate, a low acoustic velocity film, and an IDT electrode. A cut angle ?B of the piezoelectric layer at which a Rayleigh wave spurious response is locally reduced or minimized is determined from a wavelength of the IDT electrode, a film thickness of the IDT electrode, a specific gravity of the IDT electrode, an electrode duty, a thickness of the piezoelectric layer, and a film thickness of the low acoustic velocity film. The Cut angle of the piezoelectric layer satisfies a relationship of ?B?4????B+4.

Abstract: An acoustic wave filter device includes a first band pass filter including a first acoustic wave resonator connected between an antenna terminal and a first signal terminal and having a first pass band, and a second band pass filter connected with the antenna terminal and having a second pass band on a higher side of the first pass band. The first acoustic wave resonator includes a substrate on a surface of which a piezoelectric thin film is provided, an IDT electrode provided on the substrate, and reflectors. At least a pitch of some electrode fingers is different from a pitch of other electrode fingers in at least one of the IDT electrode and the reflectors of the first acoustic wave resonator on a side closest to the antenna terminal.

Abstract: A multiplexer is provided on a mounting substrate and includes a duplexer with first and second bandpass filters, and at least one bandpass filter other than the duplexer. The first and second bandpass filters respectively include first and second multilayer bodies that are different components. Configurations of the first and second multilayer bodies are different from each other such that a frequency range of high-order mode spurious radiation generated in the duplexer and a pass band of the bandpass filter other than the duplexer is different from each other.

Abstract: A multiplexer includes filters on one principal surface of a mounting substrate and having mutually different frequency bands, and an inductance element which is incorporated in the mounting substrate and one end of which is connected to one end of the filter. The other end of the inductance element and one end of each of the filters, are connected to each other at a common connection point. The inductance element is defined by spiral wiring conductors disposed in first and second wiring layers provided in an inner layer of the mounting substrate. The mounting substrate includes third and fourth wiring layers which are adjacent to the first and second wiring layers, and in which no ground pattern is provided in a portion corresponding to a formation region of the inductance element.