Design of High Power Supply Rejection and Low Temperature Drift Voltage Bandgap Reference

Based on a CSMC 0.5 μm BCD process, a high power supply rejection and low temperature drift bandgap voltage reference is proposed for the application of system-on-chip. By introducing a pseudo-power supply and generating a voltage reference in a negative feedback loop, the power supply rejection of the reference is improved. This voltage reference provides a PSR of -177.6 dB at dc and -82.7 dB at 1MHz. Additionally, the temperature coefficient of this circuit achieves 5.76×10^-6/℃ covering a range of -55~125℃.