Threshold-based voltage reference with pn- junction temperature compensation

Abstract

A new voltage reference with output dependent upon the threshold voltage of an NMOS transistor is introduced. A low temperature coefficient is achieved by using a pn-junction PTAT current generator to compensate for the negative temperature coefficient of the threshold voltage. Implemented in a standard 0.6µm CMOS process with an output of 1.67V, it has a temperature coefficient of 4.9ppm/°C over a 195 °C range.