A 0.885ppm/°C digitally calibrated bandgap voltage reference with robust start-up circuit

Abstract

A low-voltage, low temperature coefficient (TC) bandgap voltage reference (BGR) with robust start-up circuit is designed using a standard CMOS 0.18µm process. The TC is adjusted by a digitally-controlled calibration scheme. A novel and robust start-up circuit is proposed for both successful start-up behavior and TC calibration according to the operation state of the BGR. The simulation results show that a reference voltage of 604mV is obtained with a quite low TC of 0.885ppm/°C, while its power consumption is only 303µW under 1.8V supply voltage.