Amplifier circuit and related method

A circuit, comprising:

• a first signal splitter coupled to an input pre-amplifier and configured to receive an input signal, the first signal splitter comprising a first passive splitter network and a first splitter amplifier, wherein the first passive splitter network is configured to forward a first portion of the input signal towards a first amplifier and a second portion of the input signal towards the first splitter amplifier, and wherein the first portion of the input signal and the second portion of the input signal are a majority portion and a minority portion, respectively, of the input signal;
• at least one secondary signal splitter, wherein the at least one secondary signal splitter is configured to receive a respective input signal coming from the first splitter amplifier in the first signal splitter and comprises a secondary passive splitter network configured to forward a first portion of the respective input signal towards a respective secondary amplifier, and a second portion of the respective input signal towards a respective further secondary amplifier, wherein the first portion of the respective input signal and the second portion of the respective input signal are a majority portion and a minority portion, respectively, of the respective input signal, and wherein the secondary passive splitter networks are implemented via a Wilkinson topology;
• and
• combiner circuitry coupled to the first amplifier, the respective secondary amplifier and the respective further secondary amplifier, wherein the combiner circuitry is configured to provide at an output node a combined output signal combining an output signal from the first amplifier, an output signal from the respective secondary amplifier, and an output signal from the respective further secondary amplifier.

A method of operating a circuit, the circuit comprising an input pre-amplifier, a first signal splitter including a first passive splitter network and a first splitter amplifier, at least one secondary signal splitter including a secondary passive splitter network, and combiner circuitry coupled to the first splitter amplifier, a respective secondary amplifier and a respective further secondary amplifier, the method comprising:

• applying an input signal to the input pre-amplifier having the first signal splitter coupled thereto;
• forwarding, by the first passive splitter network, a first portion of the input signal towards a first amplifier and a second portion of the input signal towards the first splitter amplifier;
• receiving, by the at least one secondary signal splitter, a respective input signal coming from the first splitter amplifier in the first signal splitter;
• forwarding, by the secondary passive splitter network, a first portion of the respective input signal towards the respective secondary amplifier, and a second portion of the respective input signal towards the respective further secondary amplifier;
• operating the circuit in a first operating mode, wherein the first amplifier is active and the first splitter amplifier in the first signal splitter is inactive, and wherein the at least one secondary signal splitter does not receive the respective input signal coming from the first splitter amplifier in the first signal splitter;
• operating the circuit in at least one second operating mode, wherein both the first amplifier and the first splitter amplifier in the first signal splitter are active while the respective secondary amplifier and the respective further secondary amplifier are activated at a respective back-off point;
• and
• providing, by the combiner circuitry at an output node a combined output signal combining an output signal from the first amplifier, an output signal from the respective secondary amplifier, and an output signal from the respective further secondary amplifier.