Pico Watt sub-threshold CMOS voltage reference circuit

Abstract

This paper presents a simple Pico Watt reference circuit with the output voltage of 263.1mV using sub-threshold operation of MOSFETs at supply voltage of 0.7V. Proposed circuit consumes merely 400pW of power at room temperature and it is designed using standard TSMC 0.18µm technology. Reference voltage is provided by subtracting the 0°C threshold voltage of MOSFETs. The simulation results show voltage variation of 0.32mV/V for supply voltage from 0.7V to 2.5V and about 0.4mV of temperature variation in the range of -40°C to 120°C. The active area of the proposed circuit is 500µm². Our device would be suitable for use in passive RFIDs, WSN applications and all other power-aware SOCs.