Common gate amplifier circuit and power amplifier using the same

A differential power amplifier comprising:

• a first common source amplifier circuit coupled in parallel to a second common source amplifier circuit, each of the first and second source amplifier circuits being respectively coupled to a radio frequency (RF) input terminal, and each of the first and second source amplifier circuits respectively using a source terminal as an input terminal and an output terminal of the differential power amplifier;
• and
• a first common gate amplifier circuit coupled in parallel to a second common gate amplifier circuit, each of the first and second common gate amplifier circuits having a terminal respectively coupled to the first and second common source amplifier circuits and another terminal connected to an RF output terminal, and each of the first and second common gate amplifier circuits respectively using a gate terminal as the input terminal and the output terminal of the differential power amplifier,
• wherein each of the first and second common gate amplifier circuits comprises a Doherty amplifier comprising a main power amplifier and an auxiliary power amplifier that is connected to the main power amplifier in parallel.