A five digit A/D converter
R.J. van de Plassche, R.v.d. Grift · 1977
THE APPLICATION of large scale digital integrated circuits, such as microprocessors, in the instrumentation and control area, opens a new market for low-speed-high accuracy analog-to-digital converters. The dual slope conversion principle mostly used with an MOS technology, shows some drawbacks with respect to the analog input- and voltage reference source circuits. A different .approach using the delta-sigma modulation principle in a bipolar technology will be presented in this paper. The integrated circuits contain nearly all of the necessary circuitry except the up-down counter and the timing circuit. A maximum resolution of five decades plus sign bit has been reached. Thus a certain freedom exists for the designer in determining resolution and conversion speed