Differential power amplifiers with push-pull power amplifiers and even-harmonic cancellation

Abstract

A differential power amplifier is provided and includes a first pair of transistors. A first transistor is inductively coupled to a voltage source and is connected to a node at a ground reference potential. A second transistor is inductively coupled to the node and is connected to the voltage source. Gates of the transistors are configured to receive an AC signal with a fundamental frequency. Drain of the first and second transistors are respectively first and second output nodes. The output nodes provide a first differential output. A capacitor is connected between the output nodes and provides a pathway for cancellation of even harmonic signals of the fundamental frequency. A second pair of transistors provides a second differential output. A first inductor is connected between the output nodes. A second inductor is connected between output nodes of the second pair of transistors. A combiner is inductively coupled to the inductors.