A sub-1V low-noise bandgap voltage reference

A sub-1 V bandgap voltage reference is presented. The topology allows the reference to operate with low voltage supply, by employing reverse bandgap voltage generation. It also has attractive low-noise feature, without the use of any large external filtering capacitors. Theoretical analysis and experimental results show that the output noise spectral density is 40 nV/rectangle Hz with a peak-to-peak output noise in 0.1 to 10 Hz band of 4 rectangle V. The reference has a mean output voltage of 190.9 mV at room temperature. Temperature coefficient of the reference voltage in rectangle 40 degrees C to +125 degrees C range is 11 ppm/degrees C (mean) with a standard deviation of 5 ppm/degrees C. The design is compatible with most CMOS and BiCMOS fabrication processes.