Low Power Temperature Compensated CMOS Current Reference

Abstract

This paper describes a new circuit of a temperature-compensated CMOS current reference. The temperature dependency of the output current has been compensated by the addition of two currents which have exactly opposite temperature dependencies. Using a simple circuit, an appreciably low value of temperature drift of the output current has been obtained. The operation principle of the circuit has been described and the performance has been observed through computer simulations. The technology used is UMC 0.18μM with supply voltage of 1V. The current reference shows a temperature drift of 190ppm/0C in the temperature range of -400C to +1200C with a minimal power consumption of 80μW. This current reference can be used in some consumer systems like video & image processing, signal processing applications, RF circuits etc.