摘要:
An antenna sharer with both low loss and sharp attenuation characteristic in a wide band is achieved. Antennal sharer 1 of the present invention includes first filter 3 for passing a signal in the first frequency band, and second filter 4 for passing a signal in the second frequency band higher than the first frequency band. First filter 3 includes a ladder filter that includes first series resonator 6 and second series resonator 7 with an antiresonant frequency point higher than antiresonant frequency of first series resonator. Electromechanical coupling coefficient of first series resonator 6 is smaller than electromechanical coupling coefficient of second series resonator 7.
摘要:
An antenna sharer with both low loss and sharp attenuation characteristic in a wide band is achieved. Antennal sharer 1 of the present invention includes first filter 3 for passing a signal in the first frequency band, and second filter 4 for passing a signal in the second frequency band higher than the first frequency band. First filter 3 includes a ladder filter that includes first series resonator 6 and second series resonator 7 with an antiresonant frequency point higher than antiresonant frequency of first series resonator. Electromechanical coupling coefficient of first series resonator 6 is smaller than electromechanical coupling coefficient of second series resonator 7.
摘要:
An elastic wave device includes a piezoelectric substrate, an IDT electrode disposed on the piezoelectric substrate, an internal electrode disposed on the piezoelectric substrate and connected to the IDT electrode, a support pillar disposed on the piezoelectric substrate and provided around the IDT electrode, a top panel provided on the support pillar to cover a space above the IDT electrode, an insulation protector provided to cover the support pillar and the top panel, an external electrode disposed on the insulation protector, a conductor pattern disposed on the insulation protector in order to obtain inductance, and a connection electrode provided through the insulation protector, to connect the external electrode and the internal electrode to each other.
摘要:
A multimode elastic wave device includes a pair of reflectors, and a first interdigital transducer (IDT) electrode through a fifth IDT electrode arranged between the pair of reflectors. In this configuration, each of the average of electrode-finger pitches in the first IDT electrode and the average of electrode-finger pitches in the fifth IDT electrode is smaller than both of the average of electrode-finger pitches in the second IDT electrode and the average of electrode-finger pitches in the fourth IDT electrode.
摘要:
An acoustic wave resonator includes a piezoelectric body, an IDT electrode for exciting an acoustic wave with wavelength λ, and a dielectric thin film provided so as to cover the IDT electrode. The IDT electrode includes a bus bar electrode region, a dummy electrode region, and an IDT cross region in order from outside. The film thickness of the dielectric thin film above at least one of the bus bar electrode region and the dummy electrode region is smaller than that above the IDT cross region by 0.1λ to 0.25λ. This configuration provides an acoustic wave resonator that reduces transverse-mode spurious emission.
摘要:
An acoustic wave device (5) includes a piezoelectric substrate (6) made of a lithium niobate material having the Euler angles (φ, θ, ψ), an electrode (7) disposed on the piezoelectric substrate (6) for exciting a major acoustic wave of a wavelength λ, and a protective layer (8) disposed on the piezoelectric substrate (6) to cover the electrode (7). The protective layer (8) has a thickness greater than 0.27λ. The Euler angles satisfy −100°≦θ≦−60°; 1.193φ−2°≦ψ≦1.193φ+2°; and either ψ≦−2φ−3° or −2φ+3°≦ψ.
摘要:
The present invention provides a surface acoustic wave resonator capable of improving a leak of a surface acoustic wave in the transverse direction and reducing the spurious and having superior characteristics. In a surface acoustic wave filter according to the present invention, an interdigital transducer electrode and reflector electrodes are formed on a piezoelectric substrate, and a SiO2 thin film is formed on at least a portion of the interdigital transducer electrode. The interdigital transducer electrode includes a bus-bar electrode region, a dummy electrode region and a finger overlap region, such that the SiO2 thin film is removed from upper sections of the bus-bar electrode regions of the interdigital transducer electrode.
摘要:
An elastic wave filter has first, second, and third IDT electrodes whose wiring electrodes are connected to unbalanced signal terminal; fourth IDT electrode disposed between the first and second IDT electrodes; fifth IDT electrode disposed between the second and third IDT electrodes; and first and second balanced signal terminals connected to the wiring electrodes of fourth and fifth IDT electrodes, respectively. The ground electrodes of the first through fifth IDT electrodes are connected to the ground. Signals in opposite phase and in phase with a signal input to unbalanced signal terminal are output from first and second balanced signal terminals, respectively. The wiring electrodes of second and third IDT electrodes are adjacent to the ground electrode of fifth IDT electrode. The wiring electrode of one of first and second IDT electrodes is adjacent to the wiring electrode of fourth IDT electrode. The ground electrode of the other is adjacent to the ground electrode of fourth IDT electrode. This configuration can suppress spuriousness in the bandpass.
摘要:
An acoustic wave resonance device includes: piezoelectric substrate (1), first acoustic wave resonator (100) provided on an upper surface of piezoelectric substrate (1) and including first interdigital transducer electrode (110), and second acoustic wave resonator (200) provided on piezoelectric substrate (1) and including second interdigital transducer electrode (210). First acoustic wave resonator (100) and second acoustic wave resonator (200) are connected to each other. An overlap width of a plurality of first comb-shaped electrodes (112) forming first acoustic wave resonator (100) is larger than an overlap width of a plurality of second comb-shaped electrodes (212) forming second acoustic wave resonator (200). With such a configuration, frequencies in which a transverse mode spurious response is generated can be distributed and loss can be reduced.
摘要:
A small radio-frequency hybrid switch module is provided for switching between transmitted signals and received signals in plural frequency bands. This module includes: a laminated body including a dielectric layer; a diplexer; a switching circuit; a low pass filter (LPF); a conductive pattern provided on the dielectric layer for forming at least one of the diplexer, the switching circuit and the LPF; a surface acoustic wave (SAW) filter mounted on the laminated body; a cover provided on the SAW filter for forming a cavity which allows surface acoustic wave vibration and for hermetically sealing the cavity; and a semiconductor switching device mounted on the laminated body for forming a part of the switching circuit.