A high performance bandgap voltage reference design

Based on SMIC 0.18um N well CMOS process, a bandgap voltage reference of power circuit with high performance is designed. By means of the conventional bandgap reference, a cascade current mirror is used to increase power supply rejection and decrease the influence of circuit noise. The bias voltage of the cascade current mirror is provided by an op-amp and hence the independence of bandgap voltage on the power supply. The simulation of such a power circuit is performed by Spectre, when operating at a 3.3V power supply within the temperature range −20°C∼100°C, the results lead to a temperature coefficient of 5.223ppm/°C. Power supply rejection of the circuit can reach −81.78dB. Within the power supply ranging from 3.0V∼4.5V, it outputs a voltage of 1.1975V ± 0.5mV.The dissipation in the bandgap reference circuit is less than 0.2mW.