A design of subthreshold SRAM cell based on RSCE and RNCE

Traditional size-adjustment method of SRAM could not effectively work in the subthreshold region due to the severe penalty of cell area and supportive circuit. This paper introduces the reverse short channel effect and the reverse narrow channel effect to the size-adjustment method of the SRAM, which not only effectively solves the problem of the area penalty but also improves the static noise margin of the SRAM with fast read and write speed. Based on the SMIC 130nm process, subthreshold 10T SRAM cell is designed, and measurements indicate that the employment of the effects can promote the static noise margin by 30.5% compared to tradition ways. The SRAM can stably work at the voltage of 320mV.

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