A reconfigurable load modulation amplifier having a carrier amplifier and a peak amplifier that are coupled in parallel is disclosed. The peak amplifier provides additional power amplification when the carrier amplifier is driven into saturation. A quadrature coupler coupled between the carrier amplifier and the peak amplifier is configured to combine power from both the carrier amplifier and the peak amplifier for output through an output load terminal. The reconfigurable load modulation amplifier further includes control circuitry coupled to an isolation port of the quadrature coupler and configured to provide adjustable impedance at the isolation port of the quadrature coupler. As such, impedance at the isolation port of the quadrature coupler is tunable such that at least a carrier or peak amplifier is presented with a quadrature coupler load impedance that ranges from around about half an output load termination impedance to around about twice the output load termination impedance.

A high-speed, high-voltage gallium nitride based (GaN-based) operational amplifier (op amp) is disclosed. The combined high-speed, high-voltage capability allows the GaN-based op amp to serve as a dynamic power supply (DPS) for a radio frequency power amplifier (RFPA). When serving as a DPS for an RFPA, the GaN-based op amp is capable of supplying ampere-scale currents that accurately track rapidly-varying envelopes of non-constant envelope RF signals, thereby allowing the RFPA to convert high-bandwidth non-constant envelope RF signals to high RF output powers with high signal envelope accuracy.

Provided is a power amplification module that includes: an amplification transistor that has a constant power supply voltage supplied to a collector thereof, a bias current supplied to a base thereof and that amplifies an input signal input to the base thereof and outputs an amplified signal from the collector thereof; a first current source that outputs a first current that corresponds to a level control voltage that is for controlling a signal level of the amplified signal; and a bias transistor that has the first current supplied to a collector thereof, a bias control voltage connected to a base thereof and that outputs the bias current from an emitter thereof.

A reconfigurable load modulation amplifier having a first power amplifier (PA) configured to be supplied by a first drain voltage and a second PA coupled in parallel with the first PA, wherein the second PA is configured to be supplied by a second drain voltage is disclosed. The reconfigurable load modulation amplifier includes a quadrature coupler configured to combine power from both the first PA and the second PA for output through an output port. Also included is control circuitry configured to set at least one of the first drain voltage and the second drain voltage such that the first drain voltage is different than the second drain voltage. In at least one embodiment, the control circuitry is further configured to dynamically adjust at least one of the first drain voltage and the second drain voltage such that the first drain voltage is different than the second drain voltage.

A power supply apparatus for a power amplifier includes a converter configured to convert input power into driving power for the power amplifier, a detector configured to transfer the driving power from the converter to the power amplifier, including an inductor formed on a detection path of the driving power, and configured to detect power information regarding the driving power to generate a detected signal, and a controller configured to control power conversion of the converter based on an envelope signal of a signal input to the power amplifier and the detected signal.

There is provided an output stage comprising: a phase splitter for receiving an input signal and for generating first and second drive signals of opposite phase in dependence thereon; a DC offset signal generator for generating a DC offset signal; an adder for adding the DC offset signal to the first drive signal to provide a first modified drive signal; a subtractor for subtracting the DC offset signal from the second drive signal to provide a second modified drive signal; a first drive transistor associated with a first power supply voltage, for generating a first output signal in dependence on the first modified drive signal; a second drive transistor associated with a second power supply voltage, for generating a second output signal in dependence on the second modified drive signal; and a combiner for combining the first and second output signals to generate a phase combined output signal.

Apparatus and methods for capacitive load reduction are disclosed. In one embodiment, a power amplifier system includes a plurality of power amplifiers and an envelope tracking module for generating a supply voltage for the power amplifiers. The power amplifier system further includes a switch and a decoupling capacitor operatively associated with a first power amplifier of the system. The switch is configured to electrically float an end of the decoupling capacitor when the first power amplifier is disabled so as to reduce capacitive loading of the envelope tracker and to operate as a dampening resistor when the power amplifier is enabled so as to improve the stability of the system.

A method and system for modulating a drain supply voltage of a power amplifier are disclosed. A low pass envelope of a dual band modulated signal input to the power amplification system is determined. The determined low pass envelope is amplified. A drain supply of the power amplifier is modulated based on the amplified determined low pass envelope.

A power amplifier is described. The power amplifier including at least a first amplifier stage, and at least a first tunable matching network. The first tunable matching network is configured to couple between a first impedance and a second impedance. The first matching network including at least one first set of metal oxide semiconductor variable capacitor arrays.

Optimization methods via various circuital arrangements for amplifier with variable supply power are presented. In one embodiment, a switch can be controlled to include or exclude a feedback network in a feedback path to the amplifier to adjust a response of the amplifier dependent on a region of operation of the amplifier arrangement (e.g. linear region or compression region).