A 54-GHz 23.3%-PAE CMOS power amplifier using dual-gated transistors

Abstract

A 54-GHz two-stage pseudo-differential common source power amplifier (PA) is implemented using dual-gated transistors (DGT). DGT structure is able to enhance both the linearity and back-off efficiency without consuming extra dc power. The nonlinear characteristics of the transistor can be compensated by adjusting the gate width and overdrive voltage of each transistor in the DGT. Besides, the dc power consumption of the DGT amplifier scales with the amplitude of the input signal, resulting in enhanced PAE at back-off. Fabricated in a 65-nm CMOS process, the measured small-signal gain of the 0.5 × 0.98mm² PA is 17dB at 52GHz while consuming 24mW from a 1-V supply. The maximum saturated output power is 10.5dBm with a peak PAE of 23.3% measured at 54GHz; the measured output power and PAE at 1-dB compression is 7.6dBm and 17%, respectively.