A two-dimension half-select free 12T SRAM cell with enhanced write ability and read stability for bit-interleaving architecture

This paper proposes a two-dimension half-select free 12T SRAM cell suitable for the bit-interleaving structure. The proposed cell utilizes a data-aware power-cutting method and a decoupled read port as built-in assists to enhance the write margin (WM) and read static noise margin (RSNM) separately. In addition, it realizes two-dimension half-select (HS) free via two technologies, helping bit-interleaving architecture minimize the occurrence of multi-bits soft errors effectively. First, a cross-point-activated wordline successfully isolates the HS disturb in row and column dimensions. Second, a spare pull-up PMOS improves the robustness of column-dimension HS cells, which is lacking by the previous power-cutting structures. Monte Carlo simulations based on SMIC 55nm process confirm the robustness of row and column HS cells. The 12T cell supports a minimum VDD of 0.4V with the proposed methods, 0.3V less than the 6T cell. It improves the WM and RSNM by 2.9x and 14.17x compared to the 6T cell at 0.4V. Meanwhile, it reduces the write power consumption, read power consumption, and leakage power consumption by 52.2%, 4.5%, and than cell at 0.7V.