A Low-temperature-coefficient Bandgap Voltage Reference for Sar Adc

Abstract The paper verifies a curvature-compensated bandgap reference circuit, which generates 1.2V bandgap voltage. Bandgap voltage comprises two parts: proportional to absolute temperature (PTAT) voltage from the bandgap core and complementary to absolute temperature (CTAT) voltage from the p-n junction. Simulation results across corners show that the temperature coefficient of this architecture can be less than 3ppm/°C by using the current compensation. Test results prove that the temperature coefficient achieves 5ppm/°C. The proposed bandgap consumes a power of 2mW and occupies an area of 0.15mm2 in the 0.18μm CMOS process.