A 0.2–3.2-GHz Active Balun-LNA With 1.4–2.18-dB NF Utilizing Asymmetric Current Distribution in 28-nm CMOS

This letter presents a wideband balun low-noise amplifier (LNA) with a proposed asymmetric current distribution for optimizing both noise figure (NF) and power consumption. The approach for enhancing differential balance is also proposed. The wideband balun-LNA was fabricated in 28-nm CMOS technology and achieves a remarkable 1.4–2.18-dB NF over 0.2–3.2 GHz with a power consumption of 17.4 mW from 1.1-V supply voltage. <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$S_{11}$</tex-math> </inline-formula> is lower than <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$-$</tex-math> </inline-formula> 15.2 dB, and the gain is 24.4–26 dB across the operating bandwidth. The proposed balun-LNA shows an excellent FoM-II.