Ultralow Noise Figure and Broadband CMOS LNA With Three-Winding Transformer and Large Transistor
Joon‐Hyung Kim, Jeong-Taek Son, Jeong‐Taek Lim, Han‐Woong Choi, Choul‐Young Kim
Abstract
This article introduces a CMOS low noise amplifier (LNA) designed to operate within 32–46 GHz frequency range, aiming to achieve an ultralow noise figure (NF). Our primary goal is to get a broadband LNA with low NF, ensuring <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> 10 dB return loss and consistent, flat gain. These objectives were realized through the application of a three-winding transformer and multi-array transistors (large transistor) strategy. The proposed LNA circuit is manufactured using a 65-nm bulk CMOS process and its feasibility is confirmed through precise measurements. The NF of the fabricated LNA achieves 2.2–3.2 dB within 32–46 GHz. To the best of our knowledge, the LNA achieves the lowest NF at the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Q</i> -band. The gain is 19.2–21.5 dB within 32–46 GHz. The third-order input intercept (IIP <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{3}$</tex-math> </inline-formula> ) point is <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> 7.6 dBm at 38 GHz. The proposed LNA consumes 22 mW at 1 V supply voltage and has a compact core size of 0.16 mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{{2}}$</tex-math> </inline-formula> .