Robust Design Methodology for RF LNA including Corner Analysis

Abstract:
This work presents a design methodology of a competitive inductorless single-ended LNA in 65-nm standard CMOS technology. Instead of relying only on typical conditions, the method uses corners to find the optimal device sizing, anticipating variations on the implemented circuit, and hence, the design significantly improves its reliability, being able to fulfil specifications in a wider range of process deviations. Also, in addition to its robustness, the designed circuit is very effective, achieving a Noise Figure of 2.9 GHz at 5 GHz with a simple gm-enhanced common-gate amplifier thanks to a careful design window selection. The paper also describes the tradeoff-oriented design-window methodology that accomplishes the demanding specifications. Moreover, the authors provide a biasing strategy to offset the high process variability of the technology and statistical simulations show a 50 % reduction of failed samples due to process variations. The paper includes figures and statistical results from Montecarlo analysis for a more detailed description of the effect of the method and strategy employed on the complete design. Finally, a table compares the results with other similar circuits in the state-of-art.