An Ultra-Low Leakage Bitcell Structure with the Feedforward Self-Suppression Scheme for Near-Threshold SRAM

Abstract

Leakage power consumption has become a critical issue for low power Static Random-Access Memory (SRAM) design in the near-threshold regime. In this paper, an ultra-low leakage fourteen-transistor SRAM bitcell structure with the feedforward self-suppression scheme is presented. To reduce the leakage power significantly as well as maintain the data stability in hold state, a cross-coupled dynamic leakagesuppression inverter-based structure is adopted. Furthermore, the bypass scheme is employed to enable the speed modulation for bitcell read and write operations. As compared with stateof-the-art designs, a 65 nm 8kb SRAM array with the proposed bitcell structure achieves 75x leakage power, 45% write power as well as 65% read power reduction at 0.4V. Further comparisons with different processes verify up to 38k times leakage power reduction in 130nm planar process and 139x in 7nm plus FinFET process.