A communication unit includes a plurality of parallel radio frequency, RF, signal paths. Located between a first RF signal path of the plurality of parallel RF signal paths comprising at least one first RF amplifier and a second signal path comprising at least one second RF amplifier is one of a shared inductor or shared transformer. The at least one first RF amplifier is coupled to a supply voltage via a first switch and at least one second RF amplifier is coupled to the supply voltage via a second switch, and the first switch is closed that provides the supply voltage to the at least one second RF amplifier whilst the second switch is opened.

A power amplification module includes first and second amplifiers for first and second communication modes, a bypass line that bypasses the first or second amplifier, an input switch circuit that supplies a radio frequency signal to the first or second amplifier in accordance with a communication mode when a desired output level is equal to or greater than a reference level, and that supplies a radio frequency signal to the bypass line when the desired output level is less than the reference level, and an output switch circuit that outputs a first amplified signal from the first amplifier or a second amplified signal from the second amplifier in accordance with the communication mode when the desired output level is equal to or greater than the reference level, and that outputs a radio frequency signal output from the bypass line when the desired output level is less than the reference level.

A detector circuit includes a first inverter including an input node coupled via a first capacitor to a transmission path for transmitting an AC signal, the first inverter outputting an output voltage in accordance with power of the AC signal, wherein the output voltage increases with increasing temperature, a second inverter including an input node coupled to the transmission path, the second inverter outputting an output voltage in accordance with power of the AC signal, wherein the output voltage decreases with increasing temperature, a third capacitor including one electrode coupled to either an output electrode of the first inverter or an output node of the second inverter, a first resistor coupled between the output node of the first inverter and an output node of the detector circuit, and a second resistor coupled between the output node of the second inverter and the output node of the detector circuit.

Systems and methods that cancel distortion in the amplified outputs of a node by equalizing the distortion characteristics amplifiers in the node, so as to improve the effectiveness of predistortion applied to a downstream signal amplified by the node.

Thermally rugged power amplifiers and related methods. In some embodiments, a method for manufacturing a radio-frequency amplifier can include providing or forming a semiconductor substrate, and forming an array of cascoded devices on the semiconductor substrate to be capable of amplifying a signal, such that the array of cascoded devices includes a plurality of cascoded devices arranged in a first row and a plurality of cascoded devices arranged in a second row. Each cascoded device can include an input stage and an output stage arranged in a cascode configuration, and each of the first and second rows can be configured such that the output stages are positioned in a staggered orientation. The staggered arrangement of the cascoded devices in the first row can be offset relative to the staggered arrangement of the cascoded devices in the second row to avoid a direct row-to-row adjacent pair of output stages.

A power amplifier module includes an amplifier transistor and a bias circuit. A first power supply voltage based on a first operation mode or a second power supply voltage based on a second operation mode is supplied to the amplifier transistor. The amplifier transistor receives a first signal and outputs a second signal obtained by amplifying the first signal. The bias circuit supplies a bias current to the amplifier transistor. The bias circuit includes first and second resistors and first and second transistors. The first transistor is connected in series with the first resistor and is turned ON by a first bias control voltage which is supplied when the first operation mode is used. The second transistor is connected in series with the second resistor and is turned ON by a second bias control voltage which is supplied when the second operation mode is used.

Apparatus and methods for orienting power amplifiers are disclosed herein. In certain implementations, a method of determining the physical orientation of power amplifiers laid out on a printed circuit board (PCB) is provided. The method includes determining an amount of emissions radiated by a first power amplifier die that is positioned in a first orientation on the PCB. The method further includes determining an amount of emissions radiated by a second power amplifier die that is positioned in a second orientation on the PCB. The method further includes determining a third orientation of the second power amplifier die different than the second orientation, such that when the second power amplifier die is in the third orientation, the amount of emissions radiated by the first power amplifier die and the amount of emissions radiated by the second power amplifier die are distributed in different directions.

Embodiments of circuits for use with an amplifier that includes multiple amplifier paths include a first circuit and a second circuit in parallel with the first circuit. The first circuit includes a first input coupled to a first power divider output, a first output coupled to a first amplifier path of the multiple amplifier paths, and a first adjustable phase shifter and a first attenuator series coupled between the first input and the first output. The second circuit includes a second input coupled to a second power divider output, a second output coupled to a second amplifier path of the multiple amplifier paths, and a second adjustable phase shifter coupled between the second input and the second output.

An amplifier includes first, second, and third inputs to receive an RF signal, first and second amplifiers, and an input phase adjustment circuit coupling the first, second, and third inputs to the first and second amplifiers, the input phase adjustment circuit having first and second outputs coupled to the first and second amplifiers, respectively. The input phase adjustment circuit includes a pair of inputs, where the pair of inputs includes the first and second inputs, for the first output and a pair of phase adjustment paths coupling the pair of inputs to the first output, respectively. The pair of phase adjustment paths are configured to adjust a phase of the RF signal differently for the first output.

A circuit including: input and output nodes and first and second feedback nodes; a first input amplifier having an input connected to the input node and an output connected to the first feedback node; a second input amplifier having an input connected to the input node and an output connected to the second feedback node; a capacitor connecting the first feedback node and the second feedback node; an amplifier having an input connected to the first feedback node and an output connected to the output node; a base feedback amplifier with an input connected to the output node and an output connected to the first feedback node; a tunable feedback amplifier with an input connected to the output node and an output connected to the second feedback node; and a tuning circuit for varying a transconductance of the tunable feedback circuit and operational frequency of the peaking amplifier circuit.