Design of a Voltage Reference based on Subthreshold MOSFETS

This article proposed that an ultra-low power voltage reference under low supply voltage took advantage of characteristics of MOSFETS operating in the subthreshold region to meet the low power design. The circuit was designed using 0.18 CMOS process of SMIC, and simulated after layout using SPECTRE simulation tool. The results showed that good linearity can be attained in a supply voltage range of 0.9-3.0V and the output reference voltage is 600.8 +/- 0.65mV. In condition of 1.8V power supply, typical temperature coefficient is 15ppm/degrees C between 25 degrees C and 115 degrees C. Meanwhile under the same condition, the power consumption is only 0.54 at room temperature. This work can be applied to smart sensor and wearable medical equipment etc, which need low voltage and low power dissipation.