Abstract: A filter includes: a first acoustic wave filter having acoustic wave filters cascaded, an input stage of the acoustic wave filters including a first multimode filter; a second acoustic wave filter having acoustic wave filters cascaded, an input stage of these acoustic wave filters including a second multimode filter having an aperture length different from that of the first multimode filter, the second acoustic wave filter receiving an unbalanced in signal applied to the first acoustic wave filter, and having a pass band that does not overlap with that of the first acoustic wave filter.

Abstract: A surface acoustic wave device includes a piezoelectric substrate, a surface acoustic wave element composed of electrodes provided on the piezoelectric substrate and the piezoelectric substrate, a first seal resin portion provided on the piezoelectric substrate and having a cavity on the surface acoustic wave element, and an inorganic insulation film provided in contact with a surface of the piezoelectric substrate to surround the surface acoustic wave element.

Abstract: A duplexer includes: a first filter that is connected to a common terminal and a first terminal, and includes a first series-arm resonator; a second filter that is connected to the common terminal and a second terminal; a first inductor that is connected in parallel to the first series-arm resonator; a mounting unit that has the first filter and the second filter mounted thereon; a first inductor line that is provided on the mounting unit, and connects the first inductor and the first series-arm resonator; and a first terminal line that is provided on the mounting unit, and connects the first filter and the first terminal. In this duplexer, the directions of currents flowing through the first inductor line and the first terminal line cross each other.

Abstract: An elastic wave device formed by bonding at least two surface acoustic wave devices by filling a resin therebetween is disclosed. Each of surface acoustic wave (SAW) devices includes a substrate; a functioning portion configured on the substrate; a recess that forms a space portion necessary for operation of the functioning portion, and a package that covers the surface of the substrate, and side faces of the package of the at least two SAW devices, corresponding to a portion bonded by filling of the resin between at least two SAW devices, includes the at least one cutout, and a first resin covers a portion of each of the side faces, the back faces, and the front faces of the substrate of the at least two SAW devices, and the first resin is filled with in the at least one cutout on the side faces of the package.

Abstract: A piezoelectric thin-film resonator includes: a lower electrode supported by a substrate, a space being defined below the lower electrode; a piezoelectric film provided on the lower electrode and the substrate; and an upper electrode provided on the piezoelectric film so as to form a resonance portion in which the upper electrode faces the lower electrode across the piezoelectric film. At least one of the lower electrode and the upper electrode has an interconnection portion used to extract a signal from the resonance portion and located above the space. The at least one of the lower electrode and the upper electrode has a first mass per unit area in which the at least one of the lower electrode and the upper electrode contacts the piezoelectric film and a second mass per unit area in the resonance portion. The first mass per unit area is smaller than the second mass per unit area.

Abstract: An oscillator includes: oscillation units (11 through 1n) outputting oscillation signals of different frequencies; a transmission line (15) to which outputs of the oscillation units (11, 12) are connected, the transmission line having a characteristic impedance corresponding to an output impedance of an output terminal (Tout); and a low-pass filter 818) connected between the transmission line (15) and the output terminal.

Abstract: An acoustic wave device includes an acoustic wave element formed on a substrate, a first seal portion provided on the substrate so as to form a cavity above the acoustic wave element, and a second seal portion provided on the first seal portion, the first seal portion having a step so that the first seal portion has a width on a first side and another width on a second side arranged so that the first side is closer than the second side to the substrate, and the width on the first side is greater than the another width on the second side.

Abstract: A piezoelectric thin-film resonator includes: a lower electrode that is formed on a substrate; a piezoelectric film that is formed on the lower electrode; and an upper electrode that is formed on the piezoelectric film. In the piezoelectric thin-film resonator, the upper electrode has a greater film thickness than the lower electrode.

Abstract: A duplexer includes: a transmission filter and a reception filter that have different band center frequencies from each other; a phase matching circuit that performs phase matching on the transmission filter and the reception filter; and a laminated package that includes a first layer on which the transmission filter, the reception filter, and the phase matching circuit are mounted. In this duplexer, the first layer includes a first ground line pattern that is connected to a ground of the transmission filter, a second ground line pattern that is connected to a ground of the reception filter, a third ground line pattern that is connected to a ground of the phase matching circuit, and signal line patterns. The laminated package also includes a second layer that is located below the first layer. The second layer includes a partition ground line pattern that is located between the signal line patterns, a signal foot pad for external connection, and a ground foot pad.

Abstract: An acoustic wave device includes a piezoelectric substrate, comb electrodes formed above the piezoelectric substrate, and a first dielectric film provided so as to cover the comb electrodes, the first dielectric film having empty spaces associated with fingers of the comb electrodes.

Abstract: A duplexer includes an antenna terminal, a first filter connected to the antenna terminal, and a second filter connected to the antenna terminal. At least one of the first filter and the second filter is a ladder type filter in which a parallel resonator and multiple series resonators are included, one or more first inductors are respectively connected in parallel with one or more series resonators out of the multiple series resonators, and one of the one or more first inductors is connected in parallel with one of the multiple series resonators that is arranged closest to the antenna terminal.

Abstract: A piezoelectric thin-film resonator includes a substrate, a lower electrode provided on the substrate, a piezoelectric film provided on the lower electrode, and an upper electrode provided on the piezoelectric film so as to have a portion that overlaps the lower electrode across the piezoelectric film. At least a part of an outer end of the piezoelectric film is further in than an outer end of an opposing region in which the upper and lower electrodes overlap each other across the piezoelectric film.

Abstract: An acoustic wave device includes a piezoelectric substrate, a first dielectric film provided on the piezoelectric substrate, electrodes that are provided on the first dielectric film and excite an acoustic wave, and a second dielectric film that is provided so as to cover the electrodes and is thicker than the electrodes.

Abstract: A balanced filter includes: a filter that has at least one unbalanced signal terminal; a balun that is a lumped parameter balun that inputs or outputs signals with different phases generated based on a signal input or output from the unbalanced signal terminal of the filter, the balun being formed with an integrated passive device; and a mounting unit in which the filter and the balun are flip-chip mounted.

Abstract: An electronic device includes: an insulating substrate; at least one capacitor and an inductor that are formed directly on the insulating substrate; a line that connects the capacitor and the inductor from the above; and an external connecting pad unit that is made of the same conductor as the line and is disposed on the insulating substrate.

Abstract: A filter includes a filter chip, a laminated portion on which the filter chip is mounted, an input/output terminal provided in the laminated portion, a first U-shaped line pattern provided on a first layer and coupled to the filter chip, the first layer being included in the laminated portion between the filter chip and the input/output terminal, and a second U-shaped line pattern provided on a second layer to substantially overlap the first U-shaped line pattern and coupled to the first U-shaped line pattern and the input/output terminal, the second layer being included in the laminated portion between the first layer and the input/output terminal.

Abstract: A filter includes multiple piezoelectric thin-film resonators each having a substrate, a lower electrode formed on the substrate, a piezoelectric film formed on the lower electrode, and an upper electrode provided on the piezoelectric film so that the upper electrode and the lower electrode face each other across the piezoelectric film. The multiple piezoelectric thin-film resonators include a first resonator in which at least a part of an outer curved portion of the piezoelectric film of the first resonator is located further out than an outer curved portion of a region in which the upper electrode and the lower electrode face each other across the piezoelectric film.

Abstract: An acoustic wave device includes an acoustic wave element formed on a piezoelectric substrate, and a terminal that makes an electric connection with an outside of the acoustic wave device. The terminal has a protrusion electrode having a side surface coated with a coating film having a non-coating portion.

Abstract: The present invention is an oscillator including: first transistors outputting oscillation signals of different oscillation frequencies to collectors; a common node to which outputs of emitters of the first transistors are connected and input; a feedback circuit feeding an output of the common node to bases of the first transistors; and isolation circuits that are respectively provided between the emitters of the first transistors and the common node and cut off high frequency components from the common node.

Abstract: The present invention is an oscillator including: a first resonance circuit including a first variable capacitance diode having a cathode connected to a control terminal, a first capacitor and a first inductor connected between an anode of the first variable capacitance diode and ground; a second resonance circuit including a second variable capacitance diode having a cathode connected to the control terminal, a second capacitor and a second inductor connected between an anode of the second variable capacitance diode and ground; and an oscillation circuit coupled to the first and second resonance circuits and outputting an oscillation output.