A low-voltage low-power voltage reference based on subthreshold MOSFETs

In this work, a new low-voltage low-power CMOS voltage reference independent of temperature is presented. It is based on subthreshold MOSFETs and on compensating a PTAT-based variable with the gate-source voltage of a subthreshold MOSFET. The circuit, designed with a standard 1.2-/spl mu/m CMOS technology, exhibits an average voltage of about 295 mV with an average temperature coefficient of 119 ppm//spl deg/C in the range -25 to + 125/spl deg/C. A brief study of gate-source voltage behavior with respect to temperature in subthreshold MOSFETs is also reported.