Sub-1 V Supply Nano-Watt MOSFET-Only Threshold Voltage Extractor Circuit

Abstract

This work presents a self-biased MOSFET threshold volt age VTO extractor circuit. Its working principle is based on a current-voltage relationship derived from a continuous phys ical model. The model is valid for any operating condition, from weak to strong inversion, and under triode or satu ration regimes. The circuit is MOSFET-only (can be im plemented in any standard digital process) , and it operates with a power supply of less than 1 V, consuming tenths of nW. Post-layout simulation results show that the extracted VTO has an error inferior to 1.3%, when compared to the theoretical value, for a -40 to 125°C temperature range. We present variability results from Monte Carlo simulations that support the extracting behavior of the circuit with good ac curacy. The occupied silicon area is 0.0076 mm 2 in a 0.13p,m CMOS process.