Comparative study on 8T SRAM with different type of sense amplifier

Abstract

This paper presents the comparative study on 8T SRAM with different type of sense amplifier. These sense amplifiers are voltage-mode sense amplifier (VMSA) and current-mode sense amplifier (CMSA). The first objective of this research is to design the 8T SRAM and sense amplifier and the next objective is to identify which design has better performance in term of power, speed, stability and area. Sense amplifiers are one of the most critical circuits in the periphery of CMOS memories that plays an important role to reduce the overall sensing delay and voltage. Earlier voltage mode sense amplifiers sense the voltage difference at bit and bit lines bar but as the memory size increase the bit line and date line capacitances increases. The tools used for simulation is SILVACO EDA Gateway and SILVACO EDA Expert for layout using 0.18um technology. The results show that the CMSA has higher speed with lower delay, and low power dissipation than VMSA. But, VMSA has smaller cell area and higher noise margin than CMSA. CMSA is more suitable for high speed performance and low power circuitry and VMSA is best suited for stability and smaller design.