The disclosed technology can include a power amplifier comprising an input, an output, and a transformer. The power amplifier can include a primary inductor coil coupled to the input, a secondary inductor coil coupled to the output, and three harmonic branches coupled to the primary coil. Each branch can comprise at least one electrical component having a tunable impedance.

An architecture of radio frequency front-end includes a power amplifier module integrated duplexer (PAMiD), an antenna and at least one tunable matching network; herein, the PAMiD includes a power amplifier, and the at least one tunable matching network is located between the power amplifier and the antenna, and is configured to adjust the impedance of the output end of the power amplifier and/or the impedance of the input end of the antenna.

A power amplifier module includes first and second amplifiers, a first bias circuit, and an adjusting circuit. The first amplifier amplifies a first signal. The second amplifier amplifies a second signal based on an output signal from the first amplifier. The first bias circuit supplies a bias current to the first amplifier via a current path on the basis of a bias drive signal. The adjusting circuit includes an adjusting transistor having first, second, and third terminals. A first voltage based on a power supply voltage is supplied to the first terminal. A second voltage based on the bias drive signal is supplied to the second terminal. The third terminal is connected to the current path. The adjusting circuit adjusts the bias current on the basis of the power supply voltage supplied to the first amplifier.

A power amplifier including a cascode output stage, a bias circuit, and a temperature compensation and bias boost circuit. The cascode output stage has an input and an output and includes first and second transistors connected in series. A base of the first transistor is coupled to the input, an emitter of the first transistor is coupled to a reference potential, a collector of the first transistor is coupled to an emitter of the second transistor, and a collector of the second transistor is coupled to a supply voltage and the output. The bias circuit is coupled to the base of the second transistor. The bias boost circuit is coupled to the base of the first transistor, compensates for changes in temperature of the cascode output stage, and increases a bias current provided to the first transistor responsive to an increase in the temperature of the cascode output stage.

Two transistor rows are arranged on or in a substrate. Each of the two transistor rows is configured by a plurality of transistors aligned in a first direction, and the two transistor rows are arranged at an interval in a second direction orthogonal to the first direction. A first wiring is arranged between the two transistor rows when seen from above. The first wiring is connected to collectors or drains of the plurality of transistors in the two transistor rows. The first bump overlaps with the first wiring when seen from above, is arranged between the two transistor rows, and is connected to the first wiring.

The disclosure provides an amplifying apparatus including a plurality of amplifying circuits and an adjusting circuit. The input terminals of the amplifying circuits are coupled to a first common node. The output terminals of the amplifying circuits are coupled to a second common node. The adjusting circuit adjusts an input signal to generate an adjusted signal to the first common node; the adjusting circuit adjusts the signal of the second common node; or the adjusting circuit adjusts the input signal to generate the adjusted signal to the first common node and adjusts the signal of the second common node. The first control signal and the second control signal respectively control the amplifying circuits and the adjusting circuit to determine the gain, the linear power, and the output current of the amplifying apparatus.

An amplifier circuit includes an amplifier, a balun comprising a primary side having a primary inductance and a secondary side having a secondary inductance, the primary side coupled to an output of the amplifier, the secondary side coupled to a first output path of the amplifier circuit and a second output path of the amplifier circuit, a shunt inductance coupled to the first output path; and a compensating inductance in the balun, the compensating inductance coupled between a first node and a second node, the first node coupling the compensating inductance to the first output path, the second node coupling the secondary inductance to the compensating inductance.

The present disclosure describes a method and system for linearizing an amplifier using transistor-level dynamic feedback. The method and system enables nonlinear amplifiers to exhibit linear performance using one or more of gain control elements and phase shifters in the feedback path. The disclosed method and system may also allow an amplifier to act as a pre-distorter or a frequency/gain programmable amplifier.

Methods and apparatus for providing amplifier protection for a radio frequency (RF) front-end circuit. An example RF front-end circuit generally includes an amplifier with a gain, a first sensor configured to sense a first power (or voltage) of a first node coupled to an input of the amplifier, a second sensor configured to sense a second power (or voltage) of a second node coupled to an output of the amplifier, and logic coupled to the first and second sensors. The logic is generally configured to determine that the second power (or voltage) is outside a range based on the gain and the first power (or voltage) and to take an action to protect the amplifier based on the determination. By utilizing the techniques and apparatus described herein, protection can be provided to the amplifier(s) in an RF front-end circuit without significantly impacting the performance of the RF front-end circuit.

The present disclosure relates to an amplifier arrangement comprising a first amplifier, a second amplifier and an output combiner arranged to combine respective output signals of the first amplifier and the second amplifier into an output signal of the amplifier arrangement. An amplifier arrangement input signal is arranged as input signal to the first amplifier, and a difference signal, representing a difference between the amplifier arrangement input signal and a scaled output signal of the first amplifier, is arranged as input to the second amplifier. The output combiner is arranged to modulate the loads of the first amplifier and the second amplifier in dependence of the output signal of the second amplifier.