Computer-Controlled Analog-to-Digital Conversion

Abstract

In experiment 5, digital-to-analog and analog-to-digital conversions were discussed, and several ADC’s were constructed. Although the individual characteristics of the different ADC’s varied, all of them utilized the same basic design features shown in the block diagram of Fig. 7–1. Of the three functions shown, the voltage-comparison and reference-voltage-generation functions are relatively easy to implement, while the controller is considerably more difficult. A comparison of Figs. 7–1 and 5–9 shows that the first two functions can be performed by a single chip each (the 710 comparator and the Datei DAC-9), while the remaining components are all necessary for the control function. It is clear that Fig. 5–9 could be simplified considerably if one single unit could be found, which would handle all the necessary control and logic operations. It is in precisely such control and decision-making functions that laboratory computers are particularly useful.