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). An analog-
to-digital converter (ADC) performs the reverse operation .
Basic ideal operation
The DAC fundamentally converts finite-precision numbers
(usually fixed-point binary numbers) into a continuously varying physical
quantity, usually an analogue electrical voltage.
In an ideal DAC, the numbers are output as a sequence of impulses, that
are then filtered by a reconstruction filter. This would, in principle,
reproduce a sampled signal precisely up to the Nyquist frequency,
although a perfect reconstruction filter cannot be practically constructed
as it has infinite phase delay; and there are errors due to quantisation .
DACs are used in many other applications, such as voice
synthesizers, automatic test system, and process control actuator.
In addition, they allow computers to communicate with the real