A High-Accuracy Bandgap Reference With Compact Output Driver

A high-accuracy bandgap reference (BGR) is proposed in this brief. It employs various techniques, including base-current compensation and curvature correction, to enhance the accuracy of reference voltage. The proposed curvature correction is advantageous, since it is insensitive to process variations and reduces chip area, when compared to existing solutions. Additionally, the differential amplifiers are no longer needed in the proposed circuit, and thus it no longer has the problems of offset voltage and increased energy consumption. Besides, a compact output driver is incorporated to accommodate large load currents while ensuring a good load regulation. Additionally, an over-temperature shutdown scheme is realized to save energy at elevated temperatures. This brief is designed with a 180 nm BCD process. It realizes a temperature coefficient (TC) of smaller than 3 ppm/°C (typical) across a temperature range of $- 40\sim 85~^{\circ }$ C and at a supply voltage of 7 V. Meanwhile, a 2.2 ppm/mA load regulation is obtained for load currents varying from 0 to 100 mA at a supply voltage of 11 V. A −98.3 dB power supply rejection ratio (PSRR) is also achieved at 1 Hz. When compared with other works, the highlight of this brief is a compact output driver, an over-temperature shutdown scheme, 2 times larger range of supply voltage of 5 to 11 V, and a good TC $\leq 3$ ppm/°C (typical).