—A new sub-1-V curvature-compensated CMOS bandgap reference, which utilizes the temperature-dependent currents generated from the parasitic n-p-n and p-n-p bipolar junction transistor devices in the CMOS process, is presented. The new proposed sub-1-V curvature-compensated CMOS bandgap reference has been successfully verified in a standard 0.25- m CMOS process. The experimental results have confirmed that, with the minimum supply voltage of 0.9 V, the output reference voltage at 536 mV has a temperature coefficient of 19.5 ppm C from 0 C to 100 C. With a 0.9-V supply voltage, the measured power noise rejection ratio is 25.5 dB at 10 kHz.