Design of 0.6 V Sub-Threshold Operational Amplifier in 40 Nm Process

Operational amplifiers are one of the most useful and basic circuit building blocks for analog design. With the continuous technological advancement, most applications, especially on healthcare, demanded low voltage and low power consumption for analog front-end op-amp design. As process technology has become increasingly smaller, the MOS transistors can operate at smaller VGS, VTH, and VDS voltage. This study focuses on designing an op-amp capable of operating at 0.6 V supply voltage under low power condition using sub-threshold region of operation using the 40 nm process technology. The proposed circuit has less than 10 uW power consumption with 13 uV/° $C$ output drift. Design simulation using Monte Carlo is used due to simplicity, optimization and straight forward approximate solution.