Sigma-Delta Converters: Theory and Simulations

One of the most important pieces of instrumentation used to make measurements is the analog-digital converters. It consists of a sample and hold circuit, a one-bit ADC, a one-bit digital-to-analog converter (DAC), a summing circuit, and an analog differencing unit. The actual conversion to a multi-bit digital value is performed by some form of microprocessor that implements a digital low-pass filter. Using digital signal processing techniques it is simple to calculate the average value and output it as a binary word. It is possible to simulate a reasonably complicated system using Excel. Furthermore, Excel can help with the analysis of the system-up to a point. Using a very common and reasonably simple tool, you can learn about and experience the SigmaDelta converter.