Abstract: Amplifier having input power protection. In some embodiments, an amplifier circuit can include an input node and an output node, and an amplifier implemented between the input node and the output node. The amplifier circuit can further include a bias circuit configured to provide a bias signal to the amplifier. The amplifier circuit can further include a protection circuit configured to generate a detected voltage representative of a peak of a radio-frequency signal present at the input node. The protection circuit can be further configured to enable a protection mode when the detected voltage is greater than a first threshold value and to disable the protection mode when the detected voltage is less than a second threshold value that is less than the first threshold value.

Abstract: An isolated gate driver includes a first input terminal to receive gate information and one or more input terminals to receive configuration information. A modulation circuit generates a modulated signal having four possible states, each of the four possible states corresponding to a different unique pair of values of the gate information and the configuration information. The modulation circuit represents two of the states using on-off keying (OOK) while the configuration information is at a first value and represents two of the states as a modification to the OOK modulation based on the configuration information being at a second value. The modulated signal is sent over an isolation communication channel coupling a transmitter and receiver of the isolated gate driver.

Abstract: Systems and methods for duplexer circuits having signal leakage cancellation are provided. In one aspect, a duplexer circuit includes a transmit path splitter configured to split a radio frequency transmit signal into a pair of radio frequency transmit signals, and a receive path splitter configured to combine a pair of radio frequency receive signals. The duplexer circuit also includes an antenna path splitter configured to combine a pair of radio frequency transmit signals and split a radio frequency receive signal into the pair of radio frequency receive signals, and first and second duplexers. The first duplexer is coupled to a first leg of each of the transmit path splitter, the receive path splitter, and the antenna path splitter, and the second duplexer is coupled to a second leg of each of the transmit path splitter, the receive path splitter, and the antenna path splitter.

Abstract: An acoustic wave device comprises a piezoelectric substrate, interdigital transducer electrodes having an electrode pitch ?0, and first and second reflector gratings disposed on opposite respective sides of the interdigital transducer electrodes in a propagation direction of a main acoustic wave through the acoustic wave device, the first reflector grating having a different electrode pitch ?1 than an electrode pitch ?2 of the second reflector grating to suppress ripples in a conductance curve of the acoustic wave device.

Abstract: Aspects of this disclosure relate to a surface acoustic wave device with a vertical stack over a piezoelectric layer. The vertical stack can include a first acoustic reflector disposed on the piezoelectric layer, a second acoustic reflector disposed on the piezoelectric layer, and an interdigital transducer electrode disposed on the piezoelectric layer and positioned between the first acoustic reflector and the second acoustic reflector. The interdigital transducer electrode has a first side that is closer to the first acoustic reflector and a second side that is closer to the second acoustic reflector. A vertical arrangement of the vertical stack can be configured such that an acoustic wave propagation velocity of a first region between the first side and a first reflector is faster than an acoustic wave propagation velocity of a second region between the first side and the second side.

Abstract: Envelope tracking schemes for Doherty power amplifiers are provided herein. In certain embodiments, an envelope tracking system includes a carrier amplifier that amplifies a first radio frequency signal, a peaking amplifier that amplifies a second radio frequency signal corresponding to a delayed version of the first radio frequency signal, an envelope tracker that generates a first power supply voltage that powers the carrier amplifier, and a delay circuit that delays the first power supply voltage to generate a second power supply voltage that powers the peaking amplifier. The envelope tracker controls a voltage level of the first power supply voltage to track an envelope of the first radio frequency signal. Thus, supply modulation is used to achieve gains in linearity, efficiency, and/or other performance metrics.

Abstract: An acoustic wave device is disclosed. The acoustic wave device includes a support layer, a ceramic layer positioned over the support layer, a piezoelectric layer positioned over the ceramic layer, and an interdigital transducer electrode positioned over the piezoelectric layer. The support layer has a higher thermal conductivity than the ceramic layer. The ceramic layer can be a polycrystalline spinel layer. The acoustic wave device can be a surface acoustic wave device configured to generate a surface acoustic wave.

Abstract: Disclosed are embodiments of making a barium magnesium tantalate. The method can include providing barium magnesium tantalate and incorporating one of Ba2MgWO6, Ba8LiTa5WO24, Ba8LiTa5WO24, Ba2MgWO6, Ba3LaTa3O12, Ba8LiTa5WO24, BaLaLiWO6, Ba4Ta2WO12, Ba2La2MgW2O12, BaLaLiWO6, Sr3LaTa3O12, and SrLaTaO12 into the barium magnesium tantalate to form a solid solution having a high Q value.

Abstract: Systems and methods related to power amplification and power supply control. A power amplification control system can include an interface configured to receive a transceiver control signal from a transceiver. The power amplification control system can include a power amplifier control component configured to generate a power amplifier control signal based on the transceiver control signal from the transceiver and a power supply control component configured to generate a power supply control signal based on the transceiver control signal from the transceiver and to generate the power supply control signal based on a local control signal from the power amplifier control component.

Abstract: Aspects of this disclosure relate to an acoustic wave filter with an acoustic wave resonator arranged to concentrate a transverse spurious mode at a frequency. Such an acoustic wave resonator can have a narrow aperture to concentrate the transverse spurious mode. The transverse spurious mode can increase steepness of a skirt of the acoustic wave filter. Related methods, acoustic wave devices, multiplexers, radio frequency front ends, radio frequency modules, and wireless communication devices are disclosed.

Abstract: A baseline difference is determined between a slave line card time stamp corresponding to a slave line card frame sync signal and a master line card time stamp corresponding to a master line card frame sync signal. The slave line card generates subsequent slave line card time stamps for subsequent slave line card frame sync signals and the master line card generates subsequent master line card time stamps for subsequent master line card frame sync signals. Current differences are determined between subsequent slave line card time stamps and the subsequent master line card time stamps and the current differences are compared to the baseline difference. When a mismatch difference occurs (current difference differs from the baseline difference), the mismatch difference causes a phase-locked loop in the master line card to be adjusted or an offset to be provided to the master line card time of day counter.

Abstract: Aspects of this disclosure relate to an impedance transformation circuit for use in an amplifier, such as a low noise amplifier. The impedance transformation circuit includes a matching circuit including a first inductor. The impedance transformation circuit also includes a second inductor. The first and second inductors are magnetically coupled to each other to provide negative feedback to linearize the amplifier.

Abstract: Disclosed herein are embodiments of an enhanced resonant frequency hexagonal ferrite material and methods of manufacturing. The hexagonal ferrite material can be Y-phase hexagonal ferrite material, such as those including strontium. In some embodiments, oxides consistent with the stoichiometry of Sr3Co2Fe24O41, SrFe12O19 or CoFe2O4 can be used form an enhanced hexagonal ferrite material.

Abstract: A reconfigurable triplexer that can support more frequency bands than a traditional triplexer is disclosed. For example, the reconfigurable triplexer can handle frequencies of several hundred megahertz up to 10 gigahertz. Further, certain implementations of the reconfigurable multiplexer can reduce or eliminate frequency dead zones that exist with traditional multiplexers. The reconfigurable triplexer includes a multi-stage filter bank capable of supporting a number of frequency bands and a bypass circuit that enables the triplexer to support a variety of sets of frequencies. For instance, unlike traditional triplexers, the reconfigurable triplexer can support both frequency bands with relatively narrow spacing and frequency bands with relatively wide spacing. Further, the inclusion of the bypass circuit enables the reduction or elimination of dead zones between supported frequencies.

Abstract: Aspects of this disclosure relate to a surface acoustic wave resonator. The surface acoustic wave resonator includes a piezoelectric substrate, interdigital transducer electrodes disposed on an upper surface of the piezoelectric substrate, a dielectric temperature compensation layer disposed on the piezoelectric substrate to cover the interdigital transducer electrodes, and a dielectric passivation layer over the temperature compensation layer. The passivation layer may include an oxide layer configured to have a sound velocity greater than that of the temperature compensation layer to suppress a transverse signal transmission.

Abstract: A method for controlling a high-power drive device includes providing a current having a first predetermined current level to an output node during a first phase of a multi-phase turn-on process for the high-power drive device coupled to the output node. The method includes transitioning from the first phase to a second phase of the multi-phase turn-on process based on a first indication of a sensed voltage level on the output node during the first phase and a second indication of a time elapsed from a start of the first phase during the first phase. The method includes providing the current having a second predetermined current level to the output node during the second phase.

Abstract: Aspects of this disclosure relate to a radio frequency module with a radio frequency coupler and a coupler switching circuit. The coupler switching circuit can provide an indication of radio frequency power generated by the radio frequency coupler to a first input/output port. The coupler switching circuit can also pass an indication of radio frequency power received at the first input/output port to a second input/output port, and pass an indication of radio frequency power received at the second input/output port to the first input/output port.

Abstract: Front end systems and related devices, integrated circuits, modules, and methods are disclosed. One such packaged module includes a multi-mode power amplifier circuit in an interior of a radio frequency shielding structure and an antenna external to the radio frequency shielding structure. The multi-mode power amplifier circuit includes a stacked output stage including a transistor stack of two or more transistors. The multi-mode power amplifier circuit also includes a bias circuit configured to control a bias of at least one transistor of the transistor stack based on a mode of the multi-mode power amplifier circuit. The radio frequency shielding structure can extend above a package substrate. The antenna can be on the package substrate. Other embodiments of front end systems are disclosed, along with related devices, integrated circuits, modules, methods, and components thereof.

Abstract: A shared bus time interleaves 1 PPS signal and control and coordination information between a primary timing source and line cards that need to be synchronized using the 1 PPS signals. The shared bus utilizes 1 second frames divided into time slots. The 1 PPS signals are interleaved at predetermined locations in the frame so the delays introduced by interleaving the 1 PPS data in time can be precisely removed. While the bus is not being used for 1 PPS signals, the bus is available to send control and coordination information between the line cards and the primary timing source, avoiding the use of another system and increasing utilization of an available communication path.

Abstract: Circuits, systems, devices, and methods related to transistors with Schottky barriers are discussed herein. For example, a method of fabricating a transistor can include forming a p-well or an n-well in a substrate and forming a gate for the transistor. The method can also include doping a region within the p-well or n-well with a concentration below a threshold and forming a conductor layer on the doped region.