A curvature compensated CMOS bandgap voltage reference for high precision applications

This paper describes a high precision high order curvature compensated bandgap voltage reference in a 0.5-µm 2P3M n-well mixed signal CMOS technology. This newly proposed bandgap voltage reference utilizes a Buck’s voltage transfer cell and a temperature independent current, to provide a high order compensation of the V
BE
. Cascode structures are also introduced in this bandgap voltage reference to improve the power supply rejection ratio (PSRR). This circuit achieves 5.6 ppm/°C of temperature coefficient with temperature ranging from -20 to 100°C at 5V power supply. The variation in the output voltage of the bandgap voltage reference is 0.4mV when VDD varies from 4V to 6V.