A 180-nm X-Band Cryogenic CMOS LNA

Abstract

This letter presents the measurement results of a 180-nm complementary metal–oxide–semiconductor (CMOS) $X$ -band low-noise amplifier (LNA) at both 77 and 300 K. The designed LNA provides $S_{11}$ and $S_{22}$ below −10 dB at both temperatures within 6.4–7.4 GHz band. At 300 K, the voltage gain of the designed LNA is higher than 12.5 dB, and it provides an average noise temperature of 275 K, as well as −1 dBm IIP3. At 77 K, the LNA has approximately an 18-dB voltage gain, 78-K noise figure (NF), and −3 dBm IIP3. The presented work is the first implemented $X$ -band cryogenic CMOS LNA in the literature.