Analog-to-digital conversion is the process by which an analog (continuous) signal is converted to a digital (discrete) signal.  Two important parameters to consider in an A/D converter are resolution and range.  Resolution refers to the number of bits available to represent the signal, and range refers to the range of input signals the converter will accept.  For example, an A/D converter with 12-bit resolution has 212 = 4096 possible digital representations of the input signal.  If the range is ±10 V = 20 V, then these 4096 points are spread over 20 V, resulting in a minimum step height of 20 V / 4096 = 4.88 mV.

This simulation uses a sine wave with a user-defined amplitude as the analog signal.  The user sets the resolution and range for the A/D converter, and the resulting digital output is superimposed on the analog signal.