A design of temperature-compensated CMOS voltage reference sources with a small temperature coefficient

Abstract

A novel design for temperature-compensated CMOS voltage reference sources by using the 1st order voltage reference taking into account the property of the conventional current generator is proposed to minimize the temperature coefficient because the 2nd order voltage reference obtained by the compensated nonlinearity of the base-emitters in complementary to absolute temperature has inherent complex problems due to the large scale circuits. A temperature coefficient of the proposed voltage reference source is estimated by using the current generator, which operates at smaller or larger temperature in comparison with the optimized operating temperature. The proposed temperature-compensated CMOS voltage reference sources are simulated by using a SMIC 0.35 gm CMOS technology. The temperature coefficient, obtained from the SMIC 0.35 μm CMOS technology, is 8.35 ppm/°C in a temperature range between ’40 and 125°C. The simulated results indicate that the proposed temperature-compensated CMOS voltage reference sources by using the 1 st order voltage reference taking into account the property of the conventional current generator can be used to decrease the temperature coefficient.