Abstract: Components of a power amplifier controller may support lower voltages than the power amplifier itself. As a result, a surge protection circuit that prevents a power amplifier from being damaged due to a power surge may not effectively protect the power amplifier controller. Embodiments disclosed herein present an overvoltage protection circuit that prevents a charge-pump from providing a voltage to a power amplifier controller during a detected surge event. By separately detecting and preventing a voltage from being provided to the power amplifier controller during a surge event, the power amplifier controller can be protected regardless of whether the surge event results in a voltage that may damage the power amplifier. Further, embodiments of the overvoltage protection circuit can prevent a surge voltage from being provided to a power amplifier operating in 2G mode.

Abstract: Aspects of this disclosure relate to methods of detecting power associated with an individual carrier of a carrier aggregated signal. According to an embodiment, a method can include detecting an indication of power of a first carrier of an aggregated carrier. The method can also include, separately from detecting power of the first carrier, detecting an indication of power of a second carrier of the aggregated carrier. A power associated with a radio frequency source, such as a power amplifier, can be adjusted based on the indication of power of the first carrier.

Abstract: Field-effect transistor (FET) devices are described herein that include one or more body contacts implemented near source, gate, drain (S/G/D) assemblies to improve the influence of a voltage applied at the body contact on the S/G/D assemblies. For example, body contacts can be implemented between S/G/D assemblies rather than on the ends of such assemblies. This can advantageously improve body contact influence on the S/G/D assemblies while maintaining a targeted size for the FET device.

Abstract: An end-fire antenna for wideband low form factor applications includes a first metal layer, a second metal layer, and a dielectric layer disposed between the first and second metal layers. An open cavity formed in the dielectric layer that is filled with air, the cavity defined by a pair of sidewalls that extend from an aperture of the cavity to a rear wall of the cavity, where the depth of the aperture is defined between the aperture and the rear wall. The cavity is formed by selecting the width of the aperture of the cavity and the depth of the cavity such that the antenna achieves the same gain during operation irrespective of a variation in the thickness of the antenna.

Abstract: Disclosed herein are wireless transceivers with switches to reduce harmonic leakage. The devices are configured to transmit and receive signals in a first frequency band and a second frequency band. The devices selectively decouple a power amplifier from a duplexer to reduce harmonic leakage into a receiving system. The decoupling is accomplished using a switch, the switch being operated responsive to a band select signal indicating the second frequency band as a receive band but not a transmission band and the first frequency band as a transmission band where the first frequency band has at least one harmonic that lies within a downlink sub-band of the second frequency band.

Abstract: A radio-frequency device comprises a first transistor including a first set of fingers having a first finger-to-finger spacing in a width dimension of the first transistor, and a second transistor in a series connection with the first transistor, the second transistor including a second set of fingers having a second finger-to-finger spacing in the width dimension that is greater than the first finger-to-finger spacing.

Abstract: Disclosed are embodiments of tungsten bronze crystal structures that can have both a high dielectric constant and low temperature coefficient, making them advantageous for applications that experience temperature changes and gradients. In particular, tantalum can be substituted into the crystal structure to improve properties. Embodiments of the material can be useful for radiofrequency applications such as resonators and antennas.

Abstract: Components of a power amplifier controller may support lower voltages than the power amplifier itself. As a result, a surge protection circuit that prevents a power amplifier from being damaged due to a power surge may not effectively protect the power amplifier controller. Embodiments disclosed herein present an overvoltage protection circuit that prevents a charge-pump from providing a voltage to a power amplifier controller during a detected surge event. By separately detecting and preventing a voltage from being provided to the power amplifier controller during a surge event, the power amplifier controller can be protected regardless of whether the surge event results in a voltage that may damage the power amplifier. Further, embodiments of the overvoltage protection circuit can prevent a surge voltage from being provided to a power amplifier operating in 2G mode.

Abstract: Radio frequency (RF) communication systems with coexistence management are provided herein. In certain embodiments, a mobile device includes a first antenna, a first front end system that receives an RF receive signal from the first antenna, a first transceiver coupled to the first front end system, a second antenna, a second front end system that provides an RF transmit signal to the second antenna, and a second transceiver coupled to the second front end system. The second front end system observes the RF transmit signal to generate an RF observation signal, which is downconverted and processed by the second transceiver to generate digital observation data that is provided to the first transceiver. The first transceiver downconverts the RF receive signal to baseband, and compensates the baseband receive signal for an amount of RF signal leakage indicated by the digital observation data.

Abstract: A voltage supply system is disclosed, comprising a boost converter configured to receive an input voltage and generate a first output voltage at a first output node, a low-voltage supply circuit configured to receive the input voltage and generate a second output voltage at a second output node, and a routing circuit configured to route the first output voltage of the boost converter to the second output node during a selected condition of the input voltage.

Abstract: A switch fabrication method can include forming a plurality of elements, and connecting the elements in series between a first terminal and a second terminal, such that the elements include a first end element connected to the first terminal and a second end element connected to the second terminal. Each element can have a parameter such that the elements have a distribution of parameter values that decreases from the first end element for at least half of the elements to a minimum parameter value corresponding to an element between the first end element and the second end element. The minimum parameter value can be less than the parameter value of the second end element, and the parameter value of the first end element can be greater than or equal to the parameter value of the second end element.

Abstract: Low leakage current switch controller. In some embodiments, a controller for a radio-frequency switch can include a low-dropout regulator configured to generate a plurality of reference voltage levels for operation of a switch, or to be in a sleep mode to conserve power, based on a control signal received through a common input node. The controller can further include a mode detector in communication with the low-dropout regulator, and be configured to provide a first form of the control signal to the common input node to allow the plurality of reference levels to be generated by the low-dropout regulator, or a second form of the control signal to the common input node to put the low-dropout regulator in the sleep mode.

Abstract: Radio frequency (RF) communication systems with coexistence management are provided herein. In certain embodiments, a method of coexistence management in a mobile device includes providing an RF receive signal from a first front end system to a first transceiver, generating an RF transmit signal and an RF observation signal using a second front end system, the RF observation signal generated based on observing the RF transmit signal, generating digital observation data based on the RF observation signal using a second transceiver, downconverting the RF receive signal to generate a baseband receive signal using the first transceiver, and compensating the baseband receive signal for RF signal leakage based on the digital observation data using the first transceiver.

Abstract: Fuse programming circuits, devices and methods. In some embodiments, a fuse circuit can include a fuse pad configured to receive a voltage, a fuse having a first end coupled to the fuse pad and a second end coupled to a switching element configured to enable a current to pass from the fuse pad to a ground potential.

Abstract: A method of forming a bonding element including a first transient liquid phase (TLP) bonding element including a first material and a second material, the first material having a higher melting point than the second material, a ratio of a quantity of the first material and the second material in the first TLP bonding element having a first value, and a second TLP bonding element including the first material and the second material, a ratio of a quantity of the first material and the second material in the second TLP bonding element having a second value different from the first value.

Abstract: Apparatus and methods for multi-antenna communications are provided. In certain embodiments, a communication system includes an antenna array including a plurality of antenna elements, and a plurality of RF circuit channels each coupled to a corresponding one of the antenna elements. The plurality of RF circuit channels generate two or more analog baseband signals in response to the antenna array receiving a radio wave. The communication system further includes a controllable amplification and combining circuit that generates two or more amplified analog baseband signals based on amplifying each of the two or more analog baseband signals with a separately controllable gain, and that combines the two or more amplified analog baseband signals to generate a combined analog baseband signal.

Abstract: An example of a signal switch includes a first transistor coupled between first and second nodes, a plurality of second transistors coupled in series between the first and second nodes, in parallel with the first transistor, a third transistor coupled between the first node and a third node, and a plurality of fourth transistors coupled in series between the first and third nodes, in parallel with the third transistor. The signal switch further includes a first shunt path including a first shunt transistor and a first inductor connected in series between a reference node and a first connection point between two of the plurality of second transistors, and a second shunt path including a second shunt transistor and a second inductor connected in series between the reference node and a second connection point between two of the plurality of fourth transistors.

Abstract: Switchless carrier aggregation. In some embodiments, a carrier aggregation circuit can include a first filter configured to allow operation in a first frequency band, and a second filter configured to allow operation in a second frequency band. The circuit can further include a first signal path implemented between the first filter and an output node, with the first signal path including a plurality of amplification stages configured to amplify a first signal. The first signal path can be substantially free of switches. The circuit can further include a second signal path implemented between the second filter and the output node, with the second signal path including a plurality of amplification stages configured to amplify a second signal. The second signal path can be substantially free of switches.

Abstract: Envelope tracking can be employed to reduce power consumption of a power amplifier, but envelope tracking can introduce nonlinearities to a power amplifier. These nonlinearities can manifest themselves as noise at the output of the power amplifier. Embodiments described herein provide techniques for characterizing a parameter indicative of power amplifier noise when envelope tracking is employed. Measurement of this parameter can permit power amplifier designers to decide whether to forgo envelope tracking if a power amplifier is too susceptible to such noise, redesign the power amplifier to improve compatibility with envelope tracking, or to employ distortion compensation circuitry to reduce the noise output by the power amplifier. Counterintuitively, this distortion compensation circuitry may involve increasing the power, such as the envelope tracking power supply. However, increasing the power may be a desirable trade-off for increased linearity.

Abstract: Aspects and examples described herein provide a variable gain amplifier circuit and assembly. In one example, a variable gain amplifier circuit includes a signal input, a signal output, and a variable gain amplifier including a plurality of unit cell groups coupled between the signal input and the signal output, the variable gain amplifier configured to provide an adjustable gain to a signal received at the signal input during each of a plurality of amplify modes of the variable gain amplifier, each of the plurality of amplify modes corresponding to at least one unit cell group of the plurality of unit cell groups. A bypass path including a fixed attenuator is coupled in parallel with the variable gain amplifier between the signal input and the signal output to selectively couple the signal input to the signal output through the fixed attenuator during a bypass mode.