A/D Converter (ADC) Definition/Meaning:
Short for analog-to-digital converter. A device that can
accept an analog, i.e. continuous, signal whose amplitude lies within a given
range, and produce an equivalent digital signal, i.e. an n-bit parallel binary
word that represents this analog signal. The analog signal is "examined" at
discrete fixed intervals of time by means of a sampling process in order to
produce the digital signal. Analog signals originating from devices such as
analog sensors or tachogenerators may thus be converted into a form that can
then be processed by, say, a microprocessor.
The resolution of an A/D converter gives the smallest change in analog input
that can be discriminated by the device. If the voltage range of an n-bit A/D
converter is v, then its resolution is
V(2n - 1)
Since the resolution is finite, the conversion process introduces quantization
noise (see discrete and continuous systems).
A/D converters are available in integrated circuit form.
See also D/A converter.