Comparison of Digital Logic Circuits in Sub-threshold Region

摘要

Sub-threshold circuits involve scaling the supply voltage below the threshold voltage, where the load capacitances are charged or discharged by sub-threshold leakage currents. In this paper we discussed CMOS, Pseudo-NMOS and Pass transistor logic families operating in sub-threshold and strong inversion region. Sub-threshold circuits have been shown to consume orders of magnitude less power than the regular strong inversion circuits while maintaining comparable energy/switching as regular strong inversion circuits. However, due to lower speed of operation sub-threshold circuits remain suitable only for energy constrained systems requiring low-speed performance.