Very low noise, high accuracy, programmable voltage reference

Abstract

The design and testing of a very low noise, high accuracy, programmable voltage reference is presented in this paper. This piece of instrumentation, which can be controlled by a personal computer via the built-in RS232 interface, is intended as an alternative to batteries in the realization of automated low frequency noise measurement systems. The supply voltage ranges from 0 to 5 V with a resolution and long-term stability better than /spl plusmn/250 /spl mu/V. The power spectral density of the output voltage fluctuations is less than 10/sup -16/ V/sup 2//Hz at 100 mHz and remains below 10/sup -17/ V/sup 2//Hz above 1 Hz.