A 55nm 0.5V 128Kb cross-point 8T SRAM with data-aware dynamic supply Write-assist

This paper describes an area-efficient variation-tolerant data-aware dynamic supply Write-assist scheme for a cross-point 8T SRAM. A 128Kb test chip implemented in 55nm Standard Performance CMOS technology achieves error free full functionality without redundancy from 1.5V down to 0.5V, with area overhead of only 0.834% for the Data-Aware Write-Assist (DAWA). The superiority of the proposed scheme in area overhead and improvement in Write V_MIN and Write bit failure rate are demonstrated via comparison of measurement results with that from a base 128Kb design with Negative Bit-Line (NBL) Write-assist scheme. The maximum operating frequency is 494MHz (271MHz) at 0.6V (0.5V).