A novel design of collapsed supply and boosted bit-line swing write driver for fast write access 9T SRAM

Abstract

This work presents a collapsed supply and boosted bit-line swing (CSBBS) write driver circuit, with the specific goal of enhancing write performance. The write ability of SRAM cells is gravely affected by device parameter variations in deep sub-threshold region of operations. The collapsed supply and boosted bit-line swing are key features aimed at achieving improvements in speed and efficiency during the memory write process. In comparison to conventional, Ultra dynamic scaled supply write (UDSS), Negative charge-boosted bit line (NCBBL), and Reconfigurable negative bit line collapsed supply (RNBLCS) write driver circuits, Proposed collapsed supply and boosted bit-line swing (CSBBS) for 9T SRAM cell has optimized write access delays of 0.74X, 0.41X, 0.32X and 0.21X, improvement in write margin (WM) of 1.51X, 1.34X, 1.22X and 1.12X respectively. The CSBBS Write driver circuit is implemented using custom compiler (Synopsys) through a 28 nm BSIM4 model card for bulk CMOS. MC simulation results are monitored on Cosmoscope wave viewer (Synopsys).