0.9 V, 5 nW, 9 ppm/oC resistorless sub-bandgap voltage reference in 0.18μm CMOS

In this work a novel resistorless sub-bandgap voltage reference (BGR) is introduced. It is a self-biased and small area topology that works in the nano-ampere current consumption range, and under 1 V of power supply. The analytical behavior of the circuit is described, and simulation results for a standard 0.18 μm CMOS process are analysed. A reference voltage of 479 mV is demonstrated, with a temperature coefficient of 8.79 ppm/°C for the 0 to 125°C range, while the power consumption of the whole circuit is 4.86 nW under a 0.9 V power supply at 27 ^oC. The estimated silicon area is 0.0012 mm².