Robust subthreshold logic for ultra-low power operation

Digital subthreshold logic circuits can be used for applications in the ult ra-low power end of the design spectrum, where performance is of secondary importance, In this paper, we propose two different subthreshold logic fami lies: 1) variable threshold voltage subthreshold CMOS (VT-Sub-CMOS) and 2) subthreshold dynamic threshold voltage MOS (Sub-DTMOS) logic, Both logic fa milies have comparable power consumption as regular subthreshold CMOS logic (which is up to six orders of magnitude lower than that of normal strong i nversion circuit) with superior robustness and tolerance to process and tem perature variations than that of regular subthreshold CMOS logic.