Optimization of Bandgap Reference with High PSRR on Deep Submicron

Abstract

In this paper, optimization of a bandgap reference (BGR) with high power supply reject ration (PSRR) is presented. Voltage reference is an important core modulation in analog integrated circuit (IC), digital-analog hybrid IC and purely digital IC, such as analog-to-digital converter (ADC), digital-to-analog converter (DAC) and power management with high precision voltage or current reference, and is widely used in power managements, wireless environmental sensors and medical electronics. The folded current mirror is used to reduce the reference voltage fluctuation, and the op amp voltage feedback is used to stabilize the voltage fluctuation and MOS capacitor noise reduction. The proposed bandgap reference is based on op amp and optimized in circuit structure, layout & routing and device parameters. The optimized bandgap reference is implemented in a 180nm process, whose reference voltage generated is 1.25018V, the Temperature Coefficient (TC) is 126ppm $/^{\circ}\mathrm{C}$ in the temperature range of $- 25^{\circ}\mathrm{C}$ to $85^{\circ}\mathrm{C}$, and the PSRR is 89.5dB at low frequencies. And the active area occupies $261 \times 161 \mu m^{2}$.