An ultra low energy 9T half-select-free subthreshold SRAM bitcell

Abstract

Operating both logic and memory at subthreshold supply voltages reduces energy dissipation for portable medical devices where battery life is critical. In this paper, we propose a 9T half-select-free subthreshold bitcell that has 2.05X lower mean read energy, 12.39% lower mean write energy, and 28% lower mean leakage current than conventional 8T bitcells at the TT_0.4V_27C corner. Our bitcell also supports the bitline interleaving technique that can cope with soft errors.