A low-voltage CMOS bandgap reference circuit with improved power supply rejection

This paper presents a CMOS low-voltage bandgap reference circuit with improved power supply rejection (PSR). The analysis of the reference circuit shows the required condition to achieve high PSR. The proposed circuit incorporates a feedback loop to insure that the condition for high PSR is achieved across process variations and temperature drifts. The design has been implemented in 130nm CMOS process. It consumes 70μA from a single 1.2V supply. Simulation results show an improvement of more than 15dB in low frequency PSR due to the additional feedback loop. The theoretical and simulation results are in close agreement.