DESIGN AND ANALYSIS OF BAND GAP REFERENCE CIRCUITS

Abstract

Band Gap Reference circuits are integral part of Analog Integrated Circuits. Their function is to provide a constant reference voltage independent of temperature and supply variations. Two major building blocks of band gap reference circuits are CTAT (Complementary to absolute temperature) and PTAT (Proportional to absolute temperature). The important characteristics of CTAT circuits is the inverse relationship of their output voltage with temperature while the PTAT circuits have proportional dependence. By combining the circuits exhibiting the CTAT and PTAT nature, a constant dependence of voltage on temperature can be achieved which can be used as reference voltage for other analog circuits. Design of CTAT and PTAT circuits and their simulation using the Cadence Design Systems Software have been presented in this dissertation.