Design of an 8-cell Dual Port SRAM in 0.18-μm CMOS Technology

Abstract

Low power and low area Static Random Access Memory (SRAM) is essential for System on Chip (SoC) technology. Dual-Port (DP) SRAM greatly reduces the power consumption by full current-mode techniques for read/write operation and the area by using Single-Port (SP) cell. An 8 bit DP-SRAM is proposed in this study. Negative bit-line technique during write has been utilized for write-assist solutions. Negative voltage is generated on-chip using capacitive coupling. The proposed circuit design topology does not affect the read operation for bit interleaved architectures enabling high-speed operation. Designed in 0.18-μm CMOS process, the area is only 1.2 times of the SP-SRAM and its power is 1.3 times of the SP-SRAM when the two ports simultaneously work at the same frequency. Simulation results and comparative study of the present scheme with state of-the art conventional schemes proposed in the literature for 45 nm CMOS technology show that the proposed scheme is superior in terms of process-variations impact, area overhead, timings and dynamic power consumption. The proposed negative bit- line technique can be used to improve the write ability of 6 T Single-Port (SP) as well as 8 T DP and other multiport SRAM cells.