Abstract: Apparatus and methods for dynamic management of antenna arrays are provided herein. In certain configurations, a radio frequency (RF) system includes an antenna array including a plurality of antenna elements. The RF system further includes a plurality of signal conditioning circuits operatively associated with the antenna elements, and an antenna array management circuit that generates a plurality of enable signals that individually control activation of the signal conditioning circuits to dynamically manage the antenna array. The array of antenna elements can be dynamically managed to control a trade-off between power consumption, off-beam capture, and communication range/rate.

Abstract: Attenuators having phase shift and gain compensation circuits. In some embodiments, a radio-frequency (RF) attenuator circuit can include one or more attenuation blocks arranged in series between an input node and an output node, with each attenuation block including a local bypass path. The RF attenuator circuit can further include a global bypass path implemented between the input node and the output node. The RF attenuator circuit can further include a phase compensation circuit configured to compensate for an off-capacitance effect associated with at least one of the global bypass path and the one or more local bypass paths.

Abstract: A power amplifier impedance adjustment circuit is disclosed. In one aspect, the impedance adjustment circuit includes an input node configured to receive a radio frequency (RF) signal from a power amplifier, an output node configured to provide the RF signal to an antenna switch die, a plurality of electrical components arranged between the input node and the output node, and at least one switch configured to selectively electrically connect at least one of the electrical components to the input node and the output node. For each state of the at least one switch, the impedance adjustment circuit is configured to adjust an impedance of the power amplifier from a natural tune point in a direction towards a target tuned impedance point when viewed on a Smith chart.

Abstract: Circuitry, modules, devices, and methods for integrating front-end carrier aggregation architecture are disclosed. In some embodiments, a method can include providing a packaging substrate configured to receive a plurality of components. The method can also include providing a front-end architecture implemented on the packaging substrate, the front-end architecture including a switching assembly configured to provide switching for two or more frequency bands, the switching assembly including at least one coupler configured to couple a signal associated with the switching assembly, and a diplexer circuit including a first filter configured to pass a first frequency band, a second filter configured to pass a second frequency band, and a first electrostatic discharge network configured to dissipate electrostatic energy associated with the first and second frequency bands from the front-end architecture.

Abstract: A radio-frequency switch is disclosed, comprising a set of field-effect transistors disposed between a first node and a second node. In some embodiments, each field-effect transistor of the set of field-effect transistors has a respective source, drain, gate, and body. In some embodiments, the radio-frequency switch includes a compensation circuit coupled in parallel with the set of field-effect transistors, the compensation circuit configured to compensate a non-linearity effect generated by the set of field-effect transistors.

Abstract: Composite cascode power amplifiers for envelope tracking applications are provided herein. In certain embodiments, an envelope tracking system includes a composite cascode power amplifier that amplifies a radio frequency (RF) signal and that receives power from a power amplifier supply voltage, and an envelope tracker that generates the power amplifier supply voltage based on an envelope of the RF signal. The composite cascode power amplifier includes an enhancement mode (E-MODE) field-effect transistor (FET) for amplifying the RF signal and a depletion mode (D-MODE) FET in cascode with the E-MODE FET.

Abstract: A method includes adjusting a peaking frequency of a receiver signal path of a first integrated circuit die of the isolator product and a gain of the receiver signal path based on a predetermined peaking frequency, a predetermined gain, a first level of a diagnostic signal during a first interval, and a second level of the diagnostic signal during a second interval. The first interval and the second interval can be non-overlapping intervals.

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: Devices and methods for layout-dependent voltage handling improvement in switch stacks. In some embodiments, a switching device can include a first terminal and a second terminal, a radio-frequency signal path implemented between the first terminal and the second terminal, and a plurality of switching elements connected in series to form a stack between the second terminal and ground. The stack can have an orientation relative to the radio-frequency signal path, and the switching elements can have a non-uniform distribution of a first parameter based in part on the orientation of the stack.

Abstract: A variable attenuator circuit is disclosed. The variable attenuator circuit comprises a plurality of varactor diodes configured to attenuate an RF signal between an RF input and an RF output; a reference voltage input, and a control voltage input configured to vary the attenuation of the variable attenuator circuit based upon a control voltage. A radio frequency module and wireless device comprising said variable attenuator are also provided.

Abstract: A surface acoustic wave resonator that has at least a first resonant frequency and a second resonant frequency is disclosed. The surface acoustic wave resonator can include an interdigital transducer electrode that is positioned over a piezoelectric layer. The interdigital transducer electrode includes fingers having a first pitch. The surface acoustic wave resonator can also include a first set of reflectors that is positioned over the piezoelectric layer. The first set of reflectors includes a first number of reflectors having a second pitch. The first pitch is greater than the second pitch. The surface acoustic wave resonator can also include a second set of reflectors that is positioned over the piezoelectric layer. The second set of reflectors includes a second number of reflectors having a third pitch. The second number of reflectors is different from the first number of reflectors.

Abstract: Power amplifier having analog pre-distortion by adaptive degenerative feedback. In some embodiments, a pre-distortion circuit for an amplifier can include a transistor having an input node for receiving an input signal, an output node for providing an output signal having a gain relative to the input signal, and a common node for coupling to a ground. The pre-distortion circuit can further include a degeneration circuit implemented between the common node and the ground, with the degeneration circuit being configured to introduce a feedback response that reduces the gain when the input signal has a power level at or below a selected level. The degeneration circuit can be further configured to be disabled or provide a reduced feedback response when the input signal has a power level that exceeds the selected level.

Abstract: Reconfigurable antenna systems with ground tuning pads are provided herein. In certain embodiments, a radio frequency module includes a module substrate including a first conductive layer and a second conductive layer separated by dielectric, an antenna element formed in the first conductive layer, a plurality of tuning conductors formed in the first conductive layer, a first ground tuning pad formed in the second conductive layer and receiving a ground voltage, and a first switch. The tuning conductors include a first tuning conductor spaced apart from the antenna element on a first side of the antenna element and a second tuning conductor spaced apart from the antenna element on a second side of the antenna element. The first switch is electrically connected between the first tuning conductor and the first ground tuning pad and selectively connects the first tuning conductor to the first ground tuning pad to tune the antenna element.

Abstract: A method of making an acoustic sensor (e.g., a piezoelectric sensor for a piezoelectric microelectromechanical systems microphone) includes forming or depositing one or more piezoelectric layers to define a beam extending between a proximal portion and a distal tip (e.g., unsupported free end), the beam having a width in plan view that is greater at a location distal of the proximal portion than at the proximal portion. The method also comprises attaching the beam to a substrate in cantilever form so that the proximal portion of the beam is anchored to the substrate and the distal tip is a free unsupported end of the beam. One or more electrodes are disposed on or in the proximal portion of the beam.

Abstract: An isolated gate driver has a first portion in a first voltage domain and a second portion in a second voltage domain. The first and second portions are coupled by an isolation communication channel. The isolated gate driver transmits across the isolation communication channel a serial word containing first drive strength information and simultaneously transmits gate information with the serial word across the isolation communication channel. The gate information indicates a state of a gate signal for a transistor coupled to the second portion of the isolated gate driver. A demodulator circuit demodulates a signal containing the gate information and the drive strength information transmitted across the isolation communication channel in the serial word. A gate signal output circuit coupled to the demodulator circuit supplies the gate signal based on the gate information with a drive strength of the gate signal being based on the drive strength information.

Abstract: An apparatus for communicating across an isolation barrier includes a differential pair of input terminals. The apparatus includes a bandpass filter circuit configured to receive a received signal on the differential pair of input terminals and to provide a received differential signal on a differential pair of nodes. The apparatus includes a demodulator directly coupled to the bandpass filter circuit and configured to directly demodulate the received differential signal on the differential pair of nodes to provide a demodulated received 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: Low noise amplifiers (LNAs) are disclosed herein. In certain embodiments, an LNA includes an input balun configured to convert a single-ended radio frequency (RF) receive signal to a differential RF receive signal, an amplifier chain configured to amplify the differential RF receive signal to generate a differential amplified RF receive signal, and an output balun configured to convert the differential amplified RF receive signal into a single-ended amplified RF receive signal. The LNA's amplifier chain is operable in multiple gain modes, and includes a first differential amplification stage, a second differential amplification stage, and a third differential amplification stage.

Abstract: Reconfigurable patch antenna systems are provided herein. In certain embodiments, a mobile device includes a patch antenna configured to handle a radio frequency signal at a signal feed. The patch antenna includes a plurality of antenna segments. The front-end system further includes a plurality of switches each configured to control connection of a respective one of the first plurality of antenna segments to the first signal feed, and a control circuit configured to control the plurality of switches to provide a frequency adjustment to the patch antenna.

Abstract: Apparatus and methods for saturation detection of power amplifiers are provided. In certain embodiments, a power amplifier system includes a carrier amplifier including a first capacitor and a first gain bipolar transistor having a base configured to receive a radio frequency signal through the first capacitor. The power amplifier system further includes a saturation detector including a resistor and a detection bipolar transistor that is located within 20 ?m of the first gain bipolar transistor. The detection bipolar transistor has a base connected to the base of the first gain bipolar transistor through the resistor and a collector that generates a saturation detection current indicating a saturation of the first gain bipolar transistor.