A low-noise saturation-stacked bandgap reference for image sensor applications

A novel architecture for a bandgap voltage reference is presented in this paper. The voltage reference, designed for image sensor applications, is primarily targeted for a low-noise operation along with other practical constraints such as high power supply rejection, temperature immunity and short start-up time. The analysis and operation of the circuit is discussed and the trade-offs involved in the implementation aspects are examined. The measurement results of the fabricated circuit in a 0.35-µm CMOS process show a noise voltage level of 450 nV/sqrt(Hz) at 10 Hz, a temperature coefficient of 14 ppm/K and a PSRR of 52 dB.