Connecting digital circuitry to sensor devices
is simple if the sensor devices are inherently digital themselves. Switches,
relays, and encoders are easily interfaced with gate circuits due to the
on/off nature of their signals. However, when analog devices are involved,
interfacing becomes much more complex. What is needed is a way to
electronically translate analog signals into digital (binary) quantities,
and visa-versa. An analog-to-digital converter, or ADC, performs the
former task while a digital-to-analog converter, or DAC, performs the
latter.
