Editing Digital-to-analog converter (section)

==Overview==
[[File:Sampled.signal.svg|thumb|Sampled signal.]]
A DAC converts an [[abstract object|abstract]] finite-precision number (usually a [[fixed-point arithmetic|fixed-point]] [[binary number]]) into a  physical quantity (e.g., a [[voltage]] or a [[pressure]]). In particular, DACs are often used to convert finite-precision [[time series]] data to a continually varying physical [[signal]].

Provided that a signal's bandwidth meets the requirements of the [[Nyquist&ndash;Shannon sampling theorem]] (i.e., a [[baseband]] signal with [[Bandwidth (signal processing)|bandwidth]] less than the [[Nyquist frequency]]) and was sampled with infinite resolution, the original signal can theoretically be reconstructed from the sampled data. However, an ADC's filtering can't ''entirely'' eliminate all frequencies above the Nyquist frequency, which will [[Aliasing|alias]] into the baseband frequency range. And the ADC's digital sampling process introduces some [[quantization error]] (rounding error), which manifests as low-level noise. These errors can be kept within the requirements of the targeted application (e.g. under the limited [[Dynamic range#Human perception|dynamic range of human hearing]] for audio applications).