ADC home pageIntroductionGoalsWhy digitize?Number RepresentationDigital to AnalogAnalog to DigitalApplicationsLiterature Citations

Dual Slope ADC

Choose Subtopic

So why do it this way? Suppose that there is noise on top of the input voltage. By integrating, we average out the noise, thus getting a precise measurement of the input potential. Additionally, measuring time precisely is easier than measuring potential precisely. We can get additional bits in our measurement by using a faster clock (and thus a higher count for the same discharge time) much more easily than by adding bits to a flash or successive approximation converter. For the same mean as in the sketch above, a noisy signal would be digitized thus:

noisy dual slope

The zig-zag increase in potential is due to noise on the input signal, but that averages out over time T.

Remember that there are multiple ways to format binary numbers? Which of the common forms would be easiest to use with a dual slope ADC?




DAC Ladder Networks DAC Speed and Glitches Scheeline Group Home Page Univ. of Illinois at Urbana-Champaign Home Page Department of Chemistry Home Page Creative Commons License System Homepage University of Illinois Homepage The Camille & Henry Dreyfus Foundation Homepage Home