Low-Voltage Low-Power Curvature-Corrected Voltage Reference Circuit Using DTMOSTs

摘要

A low-voltage low power voltage reference realized in 0.35μm CMOS technology will be presented. In order to achieve two important goals of low-power high performances bandgap references realized in the newer CMOS technologies - a low supply voltage and a small value of the temperature coefficient, a modified structure using dynamic MOS transistors (equivalent with a virtually lowering of the material bandgap) and a square-root curvature-correction will be implemented. The accuracy of the output voltage will be increased using an Offset Voltage Follower Block as PTAT voltage generator, with the advantage that matched resistors are replaced by matched transistors. The low-power operation of the circuit will be achieved by using exclusively subthreshold-operated MOS devices. Experimental results confirm the theoretical estimations, showing a minimum supply voltage of 2.5V and a temperature coefficient of about 9.4 ppm/K for an extended temperature range (173K ＜ T ＜ 423K).