Abstract: Aspects of this disclosure relate to a multiplexer with an acoustic assisted trap circuit. The multiplexer includes a first acoustic wave filter and a second acoustic wave filter. The first acoustic wave filter can include a bulk acoustic wave resonator. The second acoustic wave filter can include a surface acoustic wave resonator and an impedance network. The surface acoustic wave resonator and the impedance network can together provide a trap for a harmonic associated with the first acoustic wave filter.

Abstract: Aspects of this disclosure relate to a multiplexer with an acoustic assisted trap circuit. The multiplexer includes an acoustic wave filter with an acoustic wave resonator and an impedance network that together provide a trap for a harmonic associated with another acoustic wave filter of the multiplexer. The acoustic wave filter can have an edge of a passband that is farther from the harmonic than other acoustic filters of the multiplexer.

Abstract: A bulk acoustic resonator comprises a membrane including a piezoelectric film having multiple layers of piezoelectric material. At least one of the multiple layers of piezoelectric material has a different dopant concentration than another of the multiple layers of piezoelectric material.

Abstract: Embodiments of this disclosure relate to bulk acoustic wave resonators on a substrate. The bulk acoustic wave resonators include a first bulk acoustic wave resonator, a second bulk acoustic wave resonator, a conductor electrically connecting the first bulk acoustic wave resonator to the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate.

Abstract: Aspects and embodiments disclosed herein include filter module comprising an input port to receive a radio frequency signal, a first output port connected to an antenna, a filter disposed along a fundamental signal path from the input port to the first output port, and a second output port to output a harmonic signal generated in response to the RF signal, the second output port being electrically connected to a node on the fundamental signal path via a harmonic signal path including a resonating structure configured to improve a linearity response of the filter module, the resonating structure including resonators electrically connected to each other in anti-series or anti-parallel and disposed on a piezoelectric film, a polarity direction of a first half of the resonators opposite to a polarity direction of a second half of the resonators when a voltage is applied across the piezoelectric film.

Abstract: A first acoustic wave device can have a piezoelectric layer between a first electrode and a second electrode. The first acoustic wave device can have a first shape and a first area. A second acoustic wave device can be coupled to the first acoustic wave device to at least partially cancel a second harmonic response of the first acoustic wave device. The second acoustic wave device can have a piezoelectric layer between a first electrode and a second electrode. The second acoustic wave device can have a second shape that is different from the first shape and a second area that is within a threshold amount of the first area.

Abstract: A first acoustic wave device can have a piezoelectric layer between a first electrode and a second electrode. The first acoustic wave device can have a first shape and a first area. A second acoustic wave device can be coupled to the first acoustic wave device to at least partially cancel a second harmonic response of the first acoustic wave device. The second acoustic wave device can have a piezoelectric layer between a first electrode and a second electrode. The second acoustic wave device can have a second shape that is different from the first shape and a second area that is within a threshold amount of the first area.

Abstract: A semiconductor device and a corresponding circuit for shunting current in a circuit protection configuration is disclosed. An example device includes a first semiconductor region having an anode electrical contact, a second semiconductor region having a cathode electrical contact, a third semiconductor region extending between the first semiconductor region and the second semiconductor region, the second semiconductor region and the third semiconductor region forming a PN junction therebetween, and a gate coupled to the third semiconductor region. The gate is controllable between a first mode in which additional space charges are induced in the semiconductor region to deplete the semiconductor region, and a second mode in which additional space charges are not induced in the semiconductor region.

Abstract: A bulk acoustic resonator comprises a membrane including a piezoelectric film having multiple layers of piezoelectric material. At least one of the multiple layers of piezoelectric material has a different dopant concentration than another of the multiple layers of piezoelectric material.

Abstract: Embodiments of this disclosure relate to bulk acoustic wave resonators on a substrate. The bulk acoustic wave resonators include a first bulk acoustic wave resonator, a second bulk acoustic wave resonator, a conductor electrically connecting the first bulk acoustic wave resonator to the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate.

Abstract: Aspects of this disclosure relate to a multiplexer with an acoustic assisted trap circuit. The multiplexer includes an acoustic wave filter with an acoustic wave resonator and an impedance network that together provide a trap for a harmonic associated with another acoustic wave filter of the multiplexer. The acoustic wave filter can have an edge of a passband that is farther from the harmonic than other acoustic filters of the multiplexer.

Abstract: Aspects of this disclosure relate to a multiplexer with an acoustic assisted trap circuit. The multiplexer includes a first acoustic wave filter and a second acoustic wave filter. The first acoustic wave filter can include a bulk acoustic wave resonator. The second acoustic wave filter can include a surface acoustic wave resonator and an impedance network. The surface acoustic wave resonator and the impedance network can together provide a trap for a harmonic associated with the first acoustic wave filter.

Abstract: Embodiments of this disclosure relate to bulk acoustic wave resonators on a substrate. The bulk acoustic wave resonators include a first bulk acoustic wave resonator, a second bulk acoustic wave resonator, a conductor electrically connecting the first bulk acoustic wave resonator to the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate.

Abstract: Embodiments of this disclosure relate to acoustic wave filters configured to filter radio frequency signals. An acoustic wave filter includes a first bulk acoustic wave resonator on a substrate, a second bulk acoustic wave resonator on the substrate, a conductor electrically connecting the first bulk acoustic wave resonator in anti-series with the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate. The air gap can reduce parasitic capacitance associated with the conductor. Acoustic wave filters disclosed herein can suppress a second harmonic.

Abstract: Embodiments of this disclosure relate to acoustic wave filters configured to filter radio frequency signals. An acoustic wave filter includes a first bulk acoustic wave resonator on a substrate, a second bulk acoustic wave resonator on the substrate, a conductor electrically connecting the first bulk acoustic wave resonator in anti-series with the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate. The air gap can reduce parasitic capacitance associated with the conductor. Acoustic wave filters disclosed herein can suppress a second harmonic.

Abstract: Embodiments of this disclosure relate to bulk acoustic wave resonators on a substrate. The bulk acoustic wave resonators include a first bulk acoustic wave resonator, a second bulk acoustic wave resonator, a conductor electrically connecting the first bulk acoustic wave resonator to the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate.

Abstract: A circuit includes a first transistor in a common-collector configuration and a heterojunction bipolar transistor (HBT) in a common-emitter configuration. The first transistor has a base coupled to an input node for receiving a pulsed signal. A collector of the first transistor is coupled to a first voltage source node. A base of the HBT is coupled to an emitter of the first transistor. A collector of the HBT is coupled to a second voltage source node configured to bias the HBT normally off. The HBT operating isothermally when the pulsed signal has a short-pulse width and a low duty cycle. The first transistor drives the HBT when the pulsed signal is received at the base of the first transistor to output an amplified pulsed signal at the collector of the HBT.

Abstract: A circuit includes a first transistor in a common-collector configuration and a heterojunction bipolar transistor (HBT) in a common-emitter configuration. The first transistor has a base coupled to an input node for receiving a pulsed signal. A collector of the first transistor is coupled to a first voltage source node. A base of the HBT is coupled to an emitter of the first transistor. A collector of the HBT is coupled to a second voltage source node configured to bias the HBT normally off. The HBT operating isothermally when the pulsed signal has a short-pulse width and a low duty cycle. The first transistor drives the HBT when the pulsed signal is received at the base of the first transistor to output an amplified pulsed signal at the collector of the HBT.