A 1.4 V Supply CMOS Fractional Bandgap Reference

This paper describes a bandgap reference that outputs a fraction of the silicon bandgap voltage. To simplify the design of an internal operational amplifier, the reference drives the base voltages on substrate transistors through unity-gain buffers to a fraction of a diode drop. With a 1.4 V supply, the reference produces an output of about 858 mV, which varies by 1.28 mV from -20degC to 100degC. It dissipates 162 muW and occupies 1.2 mm2in 0.35 mum CMOS.