Abstract: Disclosed are embodiments of synthetic garnet materials for use in radiofrequency applications. In some embodiments, increased amounts of gadolinium can be added into specific sites in the crystal structure of the synthetic garnet by incorporating indium, a trivalent element. By including both indium and increased amounts of gadolinium, the dielectric constant can be improved. Thus, embodiments of the disclosed material can be advantageous in both above and below resonance applications, such as for isolators and circulators.

Abstract: Voltage regulation schemes for powering multiple circuit blocks are disclosed. In certain embodiments, a front end system includes a reference voltage circuit that receives power from a power supply voltage and generates a reference voltage, a group of circuit blocks each selectively enabled by a corresponding one of a group of enable signals, and a programmable voltage regulator that generates a programmable regulated voltage based on the reference voltage and provides the programmable regulated voltage to the circuit blocks. The programmable regulated voltage has a voltage level that changes based on a selection of the circuit blocks that are enabled by the enable signals.

Abstract: Apparatus and methods for sounding reference signal (SRS) switching are provided. In certain embodiments, a controller internal to the power amplifier module initiates a sequence of instructions, in response to a single command from UE. The instructions cause a reduction in RF signal amplitude at the power amplifier output and then cause the antenna switch to actuate. Thus ensuring a single command transition and preventing over-power on the power amplifier and antenna switch. The teachings herein can be used to facilitate reduction in gap times between transitions on different antennas and avoid the use of a blank symbol before and after each SRS symbol.

Abstract: A method of fabricating an acoustic wave resonator includes forming a dielectric layer on an upper surface of a substrate, forming a lower electrode on an upper surface of the dielectric layer, forming a layer of piezoelectric material on an upper surface of the lower electrode, forming a dielectric material layer via in the dielectric layer subsequent to forming the lower electrode and the layer of piezoelectric material, and forming a conductive through substrate via passing through the substrate and the dielectric material layer via and contacting a lower surface of the lower electrode.

Abstract: Multi-mode surface acoustic wave filters are disclosed. A multi-mode surface acoustic wave filter can include a plurality of interdigital transducer electrodes that are longitudinally coupled to each other and stepped acoustic reflectors on opposing sides of the plurality of interdigital transducer electrodes. The acoustic reflectors include acoustic reflector fingers with stepped lengths.

Abstract: Aspects of this disclosure relate to a dual connectivity power amplifier system. The power amplifier system includes first and second power amplifiers that are concurrently active in a dual connectively mode. The first power amplifier is active in a different mode. A switch electrically connects the first power amplifier to different radio frequency signal paths in the dual connectivity mode and the different mode. Related methods, power amplifier modules, and wireless communication devices are disclosed.

Abstract: A switching circuit comprises a radio frequency (RF) switch, a gate resistor, a voltage source, a transmission gate, and coupling circuitry configured to couple a gate of the RF switch, a first side of the gate resistor, and the transmission gate at a first node and the voltage source, a second side of the gate resistor, and the transmission gate at a second node.

Abstract: Apparatus and methods for radio frequency (RF) switch control are provided. In certain embodiments, a level shifter for an RF switch includes a first level-shifting n-type transistor, a first cascode n-type transistor in series with the first level-shifting n-type transistor between a negative charge pump voltage and a first output that provides a first switch control signal, a first level-shifting p-type transistor, a first cascode p-type transistor in series with the first level-shifting p-type transistor between a positive charge pump voltage and the first output, and a second cascode p-type transistor between a regulated voltage and a gate of the first level-shifting n-type transistor and controlled by a first switch enable signal.

Abstract: Apparatus and methods for electrically adjustable antenna stencils for controlling antenna pattern for beamforming are provided. In certain embodiments, a mobile device includes a front-end system including a plurality of radio frequency signal conditioning circuits, an antenna array including a plurality of electrically-adjustable stencils each connected to a corresponding one of the plurality of radio frequency signal conditioning circuits, and a control circuit configured to control the plurality of electrically-adjustable stencils to control an antenna pattern of the antenna array.

Abstract: This disclosure describes amplifiers that include impedance circuits that are configured to adapt to various contexts. For example, a variable-gain amplifier can include a gain circuit configured to amplify a signal and to operate in a plurality of gain modes, and an impedance circuit coupled to the gain circuit. The impedance circuit can include an inductor and a switching-capacitive arm coupled in parallel to the inductor. The impedance circuit can be configured to operate based at least in part on a gain mode from among the plurality of gain modes.

Abstract: A circuit comprises an amplifier network including a first amplifier and a second amplifier and a first transistor having a first base. The first transistor is thermally isolated from the second amplifier. The circuit further comprises a second transistor having a second base. The second transistor is thermally linked to the second amplifier. The circuit further comprises coupling circuitry configured to couple the first base to the second base.

Abstract: Methods related to power amplification systems with adjustable common base bias. A method of implementing a power amplification system can include providing a cascode amplifier coupled to a radio-frequency input signal and coupled to a radio-frequency output. The method can further include providing a biasing component configured to apply one or more biasing signals to the cascode amplifier, the biasing component including a bias controller and one or more bias components. Each respective bias component may be coupled to a respective bias transistor.

Abstract: According to at least one aspect, a controller having a mode of operation including one of an on mode and an off mode is provided including a voltage supply node, a mode of operation signal node, a powered component, a switching device coupled in series between the voltage supply node and the powered component, a power supply detector coupled to the switching circuit, the voltage supply node, and the mode of operation signal node, the power supply detector being configured to receive a mode of operation signal indicative of the mode of operation of the controller from the mode of operation signal node, determine that the controller is in the off mode based on the mode of operation signal, and control the switching device to prevent a current from passing from the voltage supply node to the powered component responsive to determining that the controller is in the off mode.

Abstract: Apparatus and methods for adaptive power amplifier biasing are provided. In certain embodiments, a power amplifier system includes a power amplifier that provides amplification to a radio frequency (RF) signal, and a power amplifier bias control circuit that generates a bias signal of the power amplifier based on a bandwidth signal indicating a bandwidth of the RF signal. The power amplifier bias control circuit has a bandwidth that adapts to the bandwidth of the RF signal as indicated by the bandwidth signal.

Abstract: Devices and methods for operating a charge pump. In some implementations, a charge pump module includes a clock circuit configured generate to a first clock signal and a second clock signal, the first clock signal having a lower frequency than the second clock signal. The charge pump module also includes a driving circuit configured to generate a first set of clock signals based on the first clock signal and a second set of clock signals based on the second clock signal, the driving circuit coupled to the clock circuit. The charge pump module further includes a charge pump core including a set of capacitances, the charge pump core configured to charge the set of capacitances based the first set of clock signals and the second set of clock signals.

Abstract: A method for operating a gate driver system includes measuring a first parameter according to a first priority schedule synchronously to a first edge of a switching signal generated by a gate driver integrated circuit and having a variable duty cycle. The method includes after measuring the first parameter of the gate driver system and prior to a second edge of the switching signal, measuring at least a second parameter of the gate driver system according to a first round-robin schedule synchronously to the first edge of the switching signal.

Abstract: An acoustic wave resonator is disclosed. The acoustic wave resonator can include a piezoelectric layer, an interdigital transducer electrode positioned over the piezoelectric layer, a temperature compensation layer positioned over the interdigital transducer electrode, and a velocity reduction cover that extends over at least a portion of a central region of the interdigital transducer electrode and over at least a portion of the temperature compensation layer. The velocity reduction cover is arranged to cause a velocity of an acoustic wave generated by the acoustic wave resonator to be reduced.

Abstract: A method of forming a composite material for use as an isolator or circulator in a radiofrequency device comprises providing a low temperature fireable outer material, the low fireable outer material having a garnet or scheelite structure, inserting a high dielectric constant inner material having a dielectric constant above 30 within an aperture in the low temperature fireable outer material, and co-firing the lower temperature fireable outer material and the high dielectric constant inner material together at temperature between 650-900° C. to shrink the low temperature fireable outer material around an outer surface of the high dielectric constant inner material to form an integrated magnetic/dielectric assembly without the use of adhesive or glue.

Abstract: Cascode power amplifier bias circuits suitable for operating across multiple power supply domains are provided. In certain embodiments, a power amplifier system includes a cascode power amplifier and a multi-domain bias circuit that generates at least a first cascode bias voltage for the cascode power amplifier. The multi-domain bias circuit includes a coarse regulator that generates a regulated voltage based on a power supply voltage that is operable with multiple voltage levels associated with different power supply domains, a bandgap reference circuit that is powered by the regulated voltage and outputs a bandgap reference voltage, a bias voltage generator that generates multiple selectable bias voltages based on the bandgap reference voltage, and a bias voltage selector that chooses the first cascode bias voltage from amongst the selectable bias voltages.

Abstract: In some embodiments, a system can include a first stream to be opened with an arbiter device, the first stream associated with a first set of capabilities, a second stream to be opened with the arbiter device, the second stream associated with a second set of capabilities, and a wireless network architecture that determines a network messaging schedule based on the first set of capabilities and the second set of capabilities. The network messaging schedule can be sent to one or more client devices associated with the first stream or the second stream.