AN008 Sigma-delta Analog to Digital Conversion

Propeller P8X32A Application Note AN008. Perform basic sigma-delta analog to digital conversion with any of the P8X32A's eight cogs, on any pair of I/O pins, and with a few inexpensive passive components. Variations on this simple technique include calibration options, multiple analog inputs, converting from AC sources such as a microphone, and accommodating extended input voltage ranges.