A −115dB PSRR CMOS bandgap reference with a novel voltage self-regulating technique

A novel high PSRR bandgap reference is presented in this paper. Neither operational amplifiers nor any filtering capacitor are used in this design. The circuit employs a self-regulating technique to significantly suppress the supply noise over a broad frequency range. And the problem of supply coupling noise caused by the traditional start-up circuit is also avoided by an improved design. The whole circuit has been implemented in 0.18μm standard CMOS process. Experimental results demonstrate that the PSRR of the voltage reference has achieved -115dB@DC and -90dB@10MHz. A temperature coefficient of 11.68 ppm/°C is obtained in the range of -40°C to 125°C. The current consumption for voltage self-regulating circuit proposed is only 42μA.