A D-band Bi-directional Current-Reuse Common-Gate Amplifier in 45nm RFSOI

This paper presents a low-power 140-GHz bi-directional amplifier exploiting the source-drain symmetry of CMOS transistors in a common-gate amplifier. The proposed bi-directional amplifier uses symmetric inter-stage matching networks to minimize the use of lossy switches on RF signal paths. The current-reuse technique is applied to share the same supply current between two adjacent stages for low power consumption. As a proof-of-concept implementation, a prototype 140-GHz 3-stage bi-directional amplifier is implemented using a 45nm RFSOI process. The fabricated chip reports a measured peak gain of 14 dB with a 3-dB bandwidth of 21 GHz and only consumes 28.5 mW of DC power. The measured input return loss is higher than 10 dB over a bandwidth > 45 GHz, and the measured average noise figure (NF) over the 3 dB bandwidth is 6.8 dB.