Single‐ended half‐select disturb‐free 11T static random access memory cell for reliable and low power applications

Abstract

SummaryThis paper presents an 11 transistor (SEHF11T) static random access memory (SRAM) cell with high read static noise margin (RSNM) and write static noise margin (WSNM). It eliminates the write half‐select disturb using cross‐point data‐aware write word lines, which can mitigate bit‐interleaving structure to reduce multiple‐bit upset and increase soft‐error immunity. We evaluated and analyzed the effect of process, voltage, and temperature (PVT) variations on various design metrics and compared it with other cells. The SEHF11T performs fast read operation due to its higher read current and slow write operation due to its single‐ended nature. It employs the read decoupling technique to enhance the RSNM. The stacked transistors in the left/right half‐cell increase the RSNM. In addition, the WSNM is improved by eliminating the feedback of cross‐coupled inverters pair during write operation by means of power‐cutoff write‐assist technique. The proposed cell shows 1.11X higher RSNM and 1.37X higher WSNM compared to fully differential 8T (FD8T) cell. The stacked transistors in the cell reduce leakage power dissipation. The SEHF11T consumes 0.47X lower leakage power compared to FD8T at VDD = 0.7 V. Furthermore, it exhibits high reliability against PVT variations in subthreshold region and shows 1.09X narrower spread in leakage power than that of FD8T at VDD = 0.3 V.