Ultralow Noise Figure and Broadband CMOS LNA With Three-Winding Transformer and Large Transistor

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 $>$ 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 Q -band. The gain is 19.2–21.5 dB within 32–46 GHz. The third-order input intercept (IIP $_{3}$ ) point is $-$ 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 $^{{2}}$ .