Low-power subthreshold to above threshold level shifter in 90 nm process

Abstract

The use of multiple voltage domains in an integrated circuit has been widely utilized with the aim of finding a tradeoff between power saving and performance. Level shifters allow for effective interfacing between voltage domains supplied by different voltage levels. In this paper we present a low power level shifters in the 90nm technology node capable of converting subthreshold voltage signals to above threshold voltage signals. The level shifter makes use of MTCMOS design technique which gives more design flexibility, especially in low power systems. Post layout simulations indicate low power consumption and low energy consumption across process-, mismatch- and temperature variations. Minimum input voltage attainable while maintaining robust operation is found to be around 180mV, at maximum frequency of 1MHz. The level shifter employs an enable/disable feature, allowing for power saving when the level shifter is not in use.