A guided surface acoustic wave (SAW) device includes a substrate, a piezoelectric layer on the substrate, and a transducer on the piezoelectric layer. The substrate is silicon, and has a crystalline orientation defined by a first Euler angle (ϕ), a second Euler angle (θ), and a third Euler angle (ψ). The first Euler angle (ϕ), the second Euler angle (θ), and the third Euler angle (ψ) are chosen such that a velocity of wave propagation within the substrate is less than 6,000 m/s.

An antenna multiplexer comprising an input port for receiving a transmission signal, a common port, an output port, a transmit filter coupled between the input port and the common port, and a receive filter coupled between the common port and the output port. The receive filter includes a first plurality of acoustic wave resonators in a series path between the common port and the output port and a second plurality of acoustic wave resonators each coupled between the series path and ground. None of the second plurality of acoustic wave resonators are coupled to the output port. The first plurality of acoustic wave resonators including a compensation resonator that is coupled to the output port and has a capacitance that is less than an average of the capacitances of the first plurality of acoustic wave resonators. A module comprising the antenna multiplexer. An electronic device comprising the antenna multiplexer.

A method of manufacturing a packaged acoustic wave component includes forming a support substrate, forming a multi-layer piezoelectric substrate over a first side of the support substrate, and forming one or more metal layers over a second side of the support substrate that is opposite the first side of the support substrate. The method also includes forming one or more surface acoustic wave resonators or filters (including a multi-mode surface acoustic wave resonator or filter) over the multi-layer piezoelectric substrate. The method also includes forming one or more vias through the support substrate, and electrically connecting the multi-mode surface acoustic wave resonator or filter and the metal layers with the vias to provide a ground connection for the multi-mode surface acoustic wave resonator or filter.

An acoustic wave filter device includes first and second acoustic wave filters provided on a piezoelectric substrate, an insulating layer that is provided on the piezoelectric substrate and has a smaller dielectric constant than the piezoelectric substrate, a first wiring conductor electrically connected to an electrode of the first acoustic wave filter, a second wiring conductor electrically connected to an electrode of the second acoustic wave filter, the first wiring conductor and the second wiring conductor facing each other on the insulating layer in plan view, and a ground conductor located between the insulating layer and the piezoelectric substrate in a region A circumscribing the first wiring conductor and the second wiring conductor on the insulating layer in plan view.

A filter is disclosed. The filter can be a band pass filter or a band rejection filter. The filter can have bulk acoustic wave resonators. The filter can include a shunt bulk acoustic wave resonator and a series bulk acoustic wave resonator. The shunt bulk acoustic wave resonator and the series bulk acoustic wave resonator include different raised frame structures. The different raised frame structures contribute to one of the shunt bulk acoustic wave resonator or the series bulk acoustic wave resonator to have a higher quality factor below a resonant frequency than the other.

A method and apparatus for modifying or controlling a resonator connected to a signal loop having an input (18828), an output (18822), and a closed loop frequency response. The signal loop has a primary resonator (18810) having a primary frequency response. There is at least one adjustable resonator (18812) having an adjustable frequency (f) and a secondary Q-factor. An adjustable scaling block (18824) applies a gain factor (g). A controller is connected to the at least one adjustable resonator (18812) and the adjustable scaling block (18824). The controller has instructions to adjust the closed loop frequency response toward a desired closed loop frequency response by controlling the adjustable frequency (f) of the at least one adjustable resonator (18812) and the gain factor (g) of the adjustable scaling block (18824).

Certain aspects of the present disclosure generally relate to a filter, such as an acoustic resonator filter. An example filter generally includes a first series resonator coupled between a first port of the filter and a second port of the filter, the first series resonator including a first piezoelectric layer disposed between a first electrode and a second electrode of the first series resonator. The filter also includes a first shunt resonator coupled between a first node of the filter and a reference potential node of the filter, the first shunt resonator including a second piezoelectric layer disposed between a third electrode and a fourth electrode of the first shunt resonator. The first node is coupled between the two ports, and the second piezoelectric layer's thickness is greater than the first piezoelectric layer's thickness.

A filter includes first and second input/output terminals; an LC parallel resonance circuit that includes an inductor L1 and a capacitor C1 connected to each other in parallel; and an acoustic wave series resonance circuit that includes series arm resonators s1 and s2 connected to each other in series. The LC parallel resonance circuit and the acoustic wave series resonance circuit are connected to each other in series between the first input/output terminal and the second input/output terminal.

Disclosed is a radio frequency multiplexer having an M number of multiplexer branches each having an outer port terminal coupled to a common outer node, wherein M is a positive counting number. Each of the M number of multiplexer branches comprises a multi-bandpass filter configured to filter an N number of bands multiplexed by the radio frequency multiplexer to pass an individual group of N/M bands, wherein N is a positive counting number greater than one and equal to a total number of bands to be multiplexed. Each of the M number of multiplexer branches further includes an N/M number of resonator branches each having a band port terminal configured to pass a single band and an inner branch terminal coupled to an inner port terminal of the multi-bandpass filter at a common inner node.

A filter device according to an embodiment of the present disclosure includes a first filter and a second filter that are connected in parallel between a first terminal and a second terminal. The first filter includes multiple series arm resonators. The series arm resonators are disposed in series in a path from the first terminal via the first filter to the second terminal. The series arm resonators include a first series arm resonator and a second series arm resonator. Under a condition that a value obtained by dividing a difference between an antiresonance frequency and a resonance frequency of each series arm resonator by the resonance frequency is defined as a fractional bandwidth, a first fractional bandwidth of the first series arm resonator is different from a second fractional bandwidth of the second series arm resonator.