A 1.8-GHz 2-Watt Fully Integrated CMOS Push-Pull Parallel-Combined Power Amplifier Design

This paper newly presents a push-pull parallel-combined CMOS power amplifier (PA) and its analysis of operation. The proposed class-E CMOS PA incorporates the push-pull parallel-combined power devices with the 1:1:2 (two single-turn primary windings and a two-turn secondary winding) step-up on-chip transformer. The PA is fully integrated in a standard 0.18-mum CMOS technology without any external balun or matching networks. The operation of the PA with a multi-turn on-chip transformer is substantially analyzed in order to optimize the device size and its structure. Experimental data demonstrates the output power of 2-watt and the power-added efficiency (PAE) of more than 30% with a 3.3-V of power supply at 1.8 GHz. This is the new demonstration of the compact fully integrated CMOS PA with 2-watt of output power with very stable operation at 1.8 GHz range.