New Input Matching Technique for Cascode LNA in 90 nm CMOS for Millimeter Wave Applications

Low noise amplifier optimization in modern CMOS technologies is based on the noise figure minimization, preserving the input power matching. Unfortunately available analysis and design methods incorporating this design method have used very simple transistor model and are not suitable for the design in millimeter wave frequencies. In this paper we present an accurate analysis to calculate the input impedance of the inductively source-degenerated cascode LNA. Based on the analysis results we have developed analytic equations to calculate the input matching components. To compare the proposed input matching with the available ones, we have designed identical 30GHz 5mW LNA circuits, using different input matching methods. The designs have been simulated using the foundry design kit for the STMicroelectornics 90 nm CMOS process. Based on the simulation results the proposed method outperforms the available methods. Finally the circuit designed using the proposed method, has been layed out and simulated in the foundry design kit.