A 70-to-110 GHz 28-nm CMOS Low Noise Amplifier with 6.1-dB NF Minimum Using Differential Noise Optimization

This paper details the development of an ultra-broadband Low Noise Amplifier (LNA) tailored for Beyond 5G (B5G) and 6th Generation (6G) applications. The innovative design of the LNA comprises a three-stage differential common-source (CS) topology, augmented with neutralization capacitors to substantially improve both stability and gain. The circuit's input stage integrates a balun, inductors, and capacitors to ensure wideband gain optimization. Furthermore, transformer matching is employed for inter-stage connections to achieve the goal of a wideband low-noise amplifier.The LNA is fabricated using a 28-nm CMOS process and is operational across the entire W-band, spanning a frequency range of 70 to 110 GHz. This corresponds to a fractional bandwidth of 44.44%. The device achieves a minimum noise figure of 6.1 dB at 81 GHz and sustains an average noise figure of 7.5 dB across the bandwidth. Additionally, the LNA delivers an average gain of 12.5 dB while consuming 60 mW of DC power. The total area of the circuit is 0.53 mm
²
.