An ultra-low-power CMOS voltage reference generator based on body bias technique

A CMOS voltage reference, based on body bias technique, has been proposed and simulated using SMIC 0.18 μm CMOS technology in this paper. The proposed circuit can achieve a temperature coefficient of 19.4 ppm/°C in a temperature range from −20 °C to 80 °C, and a line sensitivity of 0.024 mV/V in a supply voltage range from 0.85 V to 2.5 V, without the use of resistors and any other special devices such as thick gate oxides MOSFETs with higher threshold voltage. The supply current at the maximum supply voltage and at 27 °C is 214 nA. The power supply rejection ratio without any filtering capacitor at 10 Hz and 10 kHz are −88.2 dB and −36 dB, respectively.