A Sub 1 V New Bandgap Reference Circuit with PSRR of -120dB

A Bandgap circuit capable of generating a reference voltage of less than 1V with high PSRR, low process, supply voltage and temperature sensitivity is proposed. High PSRR achieved by means of an improved current mode regulator which isolates the bandgap voltage from the variations and the noise of the power supply. The proposed circuit is implemented in a 0.35μm CMOS technology. The BGR circuit occupies 0.024 mm² of die area and consumes 90μW from a 5V supply voltage at room temperature. Experimental results demonstrate that the PSRR of the voltage reference has achieved - 120dB at frequencies up to 1kHz and -58dB@1MHz. A temperature coefficient of 60 ppm/°C is obtained in the range of -40°C to 120°C.