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 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 longitudinally coupled resonator-type surface acoustic wave filter includes a low acoustic velocity film and a piezoelectric film stacked over a high acoustic velocity component in which a bulk wave propagates at an acoustic velocity higher than an acoustic velocity of an elastic wave that propagates in the piezoelectric film. IDT electrodes are provided on one surface of the piezoelectric film. The longitudinally coupled resonator-type surface acoustic wave filter uses a SH wave. At least one of the IDT electrodes has a duty factor that is adjusted over an entire length of the one of the IDT electrodes in the direction of elastic wave propagation to suppress a Rayleigh wave spurious response.

Abstract: A ladder filter that sufficiently attenuates a signal in a frequency range in a vicinity of a pass band on a lower-frequency side of the pass band includes a plurality of series arm resonators and at least three parallel arm resonators provided in at least three respective parallel arms. One of the at least three parallel arm resonators farthest from an input terminal and an output terminal, is subjected to parallel division to include a first division resonator and a second division resonator. The second division resonator has the highest resonant frequency and the smallest electrostatic capacitance of all of the parallel arm resonators and the division 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 multiplexer includes a common terminal, a reception terminal, and transmission terminals; a reception filter between the common terminal and the reception terminal; a transmission filter between the common terminal and the transmission terminal; a transmission filter between the common terminal and the transmission terminal; a first inductor connected in series between the common terminal and the reception filter; a second inductor connected between the transmission terminal and the transmission filter; and a third inductor connected between the transmission terminal and the transmission filter. The first inductor and the second inductor couple with each other through a magnetic field, and the first inductor and the third inductor couple with each other through a magnetic field.

Abstract: A multiplexer includes filters, a common terminal with which an inductance element is connected to a connection path of the common terminal and an antenna element and a capacitance element is connected in series to the connection path, and another inductance element. An input terminal of one of the filters is connected to the common terminal via the another inductance element, and is connected to a parallel resonator. In each of the filters other than the one filter, one of the input terminal and the output terminal, which is a terminal closer to the antenna element, is connected to the common terminal, and is connected to the series resonator.

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 duplexer includes a first band-pass filter and a second band-pass filter with a pass-band lower than the first band-pass filter. The first band-pass filter includes an unbalanced surface acoustic wave filter. First, second and third signal wire electrodes and a ground wire electrode are provided on a piezoelectric substrate in the first band-pass filter, and a bridging area is provided where any one of the first, second and third signal wire electrodes bridges the ground wire electrode. A width of a portion of the signal wire electrode that opposes the ground wire electrode with an interlayer insulating film located therebetween is greater than a width of a portion of the signal wire electrode other than the bridging area so that a low-pass filter capacitor is provided.

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: 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 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: 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: In a filter device, first and second filter sections are connected in parallel between an input terminal and an output terminal. The first filter section is a longitudinally coupled resonator-type elastic wave filter including first and second inter-stage wiring lines with a two-stage cascading connection. The second filter section is a longitudinally coupled resonator-type elastic wave filter including third and fourth inter-stage wiring lines with a two-stage cascading connection. The phases of signals flowing in the third inter-stage wiring line and the second inter-stage wiring line are inverse. Terminal portions of an interdigital transducer electrode connected to the second inter-stage wiring line and an interdigital transducer electrode connected to the third inter-stage wiring line that are connected to a potential that is not a hot-side potential are connected by a virtual ground wiring line.

Abstract: In a splitter, a first duplexer including a first transmit filter and a first receive filter at a first antenna terminal and a second duplexer including a second transmit filter and a second receive filter at a second antenna terminal are connected to each other. A second transmit band of the second transmit filter and a second receive band of the second receive filter are positioned in a frequency range between a first transmit band of the first transmit filter and a first receive band of the first receive filter. Each of the second transmit filter and the second receive filter of the second duplexer includes an elastic wave filter.

Abstract: A duplexer includes a transmission filter with a ladder circuit configuration and a reception filter including a ladder filter portion connected to an antenna terminal and a longitudinally coupled resonator-type surface acoustic wave filter. In the transmission filter, a coupling capacitor is connected between an end portion of an inductor nearer to parallel arm resonators and a wiring line connecting the series arm resonators of the ladder filter portion to each other in the reception filter.

Abstract: A surface acoustic wave filter device includes surface acoustic wave filters, one of which includes a longitudinally coupled resonator-type first filter section and a longitudinally coupled resonator-type second filter section. The second filter section is electrically connected in parallel or series with the first filter section on at least one of an input signal side and an output signal side. The first filter section includes a first IDT group including three IDTs. The second filter section includes a second IDT group including three IDTs. Another surface acoustic wave filter includes a third IDT group that is cascade connected to the first filter section and the second filter section and includes IDTs arranged in order in a line in a surface acoustic wave propagation direction.

Abstract: A duplexer includes a transmission filter with a ladder circuit configuration and a reception filter. The reception filter includes a series trap element connected to an antenna terminal and a longitudinally coupled resonator-type surface acoustic wave filter. In the transmission filter, a coupling capacitance is connected between an end portion at parallel arm resonators side of an inductance and a line connecting the series trap element to the longitudinally coupled resonator-type surface acoustic wave filter in the reception filter.

Abstract: An elastic wave device includes a piezoelectric film and a high acoustic velocity member in which an acoustic velocity of a bulk wave propagating in the high acoustic velocity member is larger than an acoustic velocity of a main mode elastic wave propagating in the piezoelectric film, the piezoelectric film that is directly or indirectly laminated on the high acoustic velocity member, a first conductive film provided on the piezoelectric film, and a second conductive film that is provided on the piezoelectric film and on at least a portion of the first conductive film. A plurality of IDT electrodes including electrode fingers and busbars are provided on the piezoelectric film, at least electrode fingers of a plurality of IDT electrodes are defined by the first conductive film, and at least a portion of connection wiring with which the plurality of IDT electrodes are connected to each other is defined the second conductive film.