Instead of impulses, usually the sequence of numbers update the analogue voltage at uniform sampling intervals. Piecewise constant output of a conventional practical DAC. Digital sampling introduces quantization error that manifests as low-level noise added to the reconstructed signal. Other DAC methods (e.g., methods based on Delta-sigma modulation) produce a pulse-density modulated signal that can then be filtered in a similar way to produce a smoothly varying signal.Īs per the Nyquist–Shannon sampling theorem, a DAC can reconstruct the original signal from the sampled data provided that its bandwidth meets certain requirements (e.g., a baseband signal with bandwidth less than the Nyquist frequency). In particular, DACs are often used to convert finite-precision time series data to a continually varying physical signal.Ī typical DAC converts the abstract numbers into a concrete sequence of impulses that are then processed by a reconstruction filter using some form of interpolation to fill in data between the impulses.

The suitability of a particular DAC for an application is determined by a variety of measurements including speed and resolution.Ī DAC converts an abstract finite-precision number (usually a fixed-point binary number) into a physical quantity (e.g., a voltage or a pressure). There are many DAC architectures which have different advantages and disadvantages. Digital-to-analog conversion can degrade a signal, so conversion details are normally chosen so that the errors are negligible.ĭue to cost and the need for matched components, DACs are almost exclusively manufactured on integrated circuits (ICs). Digital video signals are converted to analog in televisions and cell phones to display colors and shades. Signals are easily stored and transmitted in digital form, but a DAC is needed for the signal to be recognized by human senses or other non-digital systems.Ī common use of digital-to-analog converters is generation of audio signals from digital information in music players. An analog-to-digital converter (ADC) performs the reverse operation. In electronics, a digital-to-analog converter ( DAC or D-to-A) is a device that converts a digital (usually binary) code to an analog signal (current, voltage, or electric charge). 8-channel digital-to-analog converter Cirrus Logic CS4382 as used in a soundcard.

What is an analog to digital converter