Page 159 - Bebop to The Boolean Boogie An Unconventional Guide to Electronics Fundamentals, Components, and Processes

Analog-to-Digital and

Digital-to-A nalog

As we began our discussions in Chapter 1 by separating the analog and

digital views of the world, it seems appropriate to close this section of the book
by reuniting them. While some systems operate solely on digital data, others
have to interact with the analog world. It may be necessary to convert an
analog input into a form that can be manipulated by the digital system, or to
transform an output from a digital system into the analog realm. These tasks are
performed by analog-to-digital (A/D) and digital-to-analog (D/A) converters,
respectively (Figure 13 - 1 ) .
Fpb

Analog-to-Digital Digital-to-Analog
Converter Digital System Converter

Analog Domain Digital Domain Analog Domain

Figure 1 3-1. Analog-to-digital (A/D) and digital-to-analog (D/A) converters

Analog-to-Dig ita1
A transducer is a device that converts input energy of one form into output
energy of another. Analog effects can manifest themselves in a variety of differ-
ent ways such as heat and pressure. In order to be processed by a digital system,
the analog quantity must be detected and converted into a suitable form by
means of an appropriate transducer called a sensor. For example, a microphone
is a sensor that detects sound and converts it into a corresponding voltage. The
analog-to-digital conversion process can be represented as shown in Figure 13-2.