Ground bounce noise reduction of low leakage 1-bit nano-CMOS based full adder cells for mobile applications

Abstract

As technology scales into the nanometer regime ground bounce noise and noise immunity are becoming important metric of comparable importance to leakage current, active power, delay and area for the analysis and design of complex arithmetic logic circuits. In this paper, low leakage 1bit full adder cells are proposed for mobile applications with low ground bounce noise and a novel technique has been introduced with improved staggered phase damping technique for further reduction in the peak of ground bounce noise. Noise immunity has been carefully considered since the significant threshold current of the low threshold voltage transition becomes more susceptible to noise. We introduced a new transistor resizing approach for 1bit full adder cells to determine the optimal sleep transistor size which reduce the leakage power and ground bounce noise. The simulation results depicts that the proposed design also leads to efficient 1bit full adder cells in terms of standby leakage power, active power, ground bounce noise and noise margin. We have performed simulations using Cadence Spectre 90nm standard CMOS technology at room temperature with supply voltage of 1V.