D-Band SiGe BiCMOS Power Amplifier With 16.8,dBm P1,dB and 17.1% PAE Enhanced by Current-Clamping in Multiple Common-Base Stages

This letter presents single-ended and differential D-band power amplifiers (PAs) in 55nm SiGe BiCMOS technology. The proposed PAs exploit the remarkable features of common-base stages for rising the power efficiency, i.e., 1) higher breakdown voltage; 2) sharp compression profile due to the enhanced linearity; and 3) supply current adapted to the signal amplitude by means of current clamping. A four-stage single-ended PA proves P1,dB = 16.8 dBm with PSAT = 17.6 dBm at 135 GHz. The PAEs at P1,dB and P1,dB-6,dB are 17.1% and 8.5%, respectively. With a differential PA, the linear output power is increased to P1,dB = 18.5 dBm with PSAT = 19.3 dBm at 135 GHz. The PAEs at P1,dB and P1,dB-6,dB are 12.6% and 6.7%, respectively. The PAs demonstrate 3x PAE improvement in the linear region against the state of the art.