A New 8T SRAM Circuit with Low Leakage and High Data Stability Idle Mode at 70nm Technology

Abstract

Memory has been facing several problems in which the leakage current is the most severe. Many techniques have been proposed to withstand leakage control such as power gating and ground gating. In this paper a new 8T SRAM cell, which adopts a single bit line scheme has been proposed to limit the leakage current as well as to gain high hold static noise margin. The proposed cell with low threshold voltage, high threshold voltage and dual threshold voltage are used to effectively reduce leakage current, and delay. Additionally, the comparison has been performed between conventional 6T SRAM cell and the new 8T SRAM cell. The proposed circuit consumes 671.22 pA leakage current during idle state of the circuit which is very less as compare to conventional 6T SRAM cell with sleep and hold transistors and with different b ratio. The proposed new 8T SRAM cell shows highest noise immunity 0.329mv during hold state. Furthermore, the proposed new 8T SRAM circuit represents minimum read and write access delays 114.13ps and 38.56ps respectively as compare to conventional 6T SRAM cell with different threshold voltages and b ratio.keywords: SRAM, static noise margin, single bit line, threshold voltage, leakage current, b ratio.