A 28-GHz 3.4-mW LNA Using Current-Reuse Technique in 65-nm CMOS

A 28-GHz low-power low-noise amplifier (LNA) in 65-nm CMOS is presented. The LNA is designed utilizing a common source (CS) single-ended stage cascaded by a differential neutralized stage, and incorporates a current-reuse technique between the two stages. Through the current-reuse technique, the power consumption of the LNA can be significantly reduced with limited deterioration in noise figure (NF). A matching network based on a weakly-coupled transformer is introduced at the input stage of the LNA. An inter-stage transformer-based balun is adopted to realize the single-ended-to-differential signal conversion and improves the bandwidth. A large capacitor is utilized inside the balun to suppress the influence of RF leakage signals and realizes current-reuse. The LNA is fabricated in a 65-nm CMOS technology. The supply voltage is 1V and the power consumption is 3.4mW. The LNA achieves a simulated peak gain of 19.1 dB at 29.3 GHz with a 3-dB bandwidth from 26.1 to 30.8 GHz. A NF of 3.57 dB is achieved at 29 GHz.