When most of us hear the term digital, we immediately think of “digital calculator” or “digital computer”. This can probably be attributed to the dramatic way that low-cost, powerful calculators and computer have become accessible to the average person. It is important to realize that calculators and computers represent only one of the many applications of digital circuits and principles. Digital circuits are used in electronic products such as video games, microwave ovens, and automobile control systems, and in test equipment such as meters, generators, and oscilloscopes. Digital techniques have also replaced a lot of the older “analog circuits” used in consumer products such as radios, TV sets, and high-fidelity sound recording and playback equipment.
In this book we are going to study the principles and techniques that are common to all digital systems from the simplest on/off switch to the most complex computer. If this book is successful, you should gain a deep understanding of how all digital systems work, and you should be able to apply this understanding to the analysis and troubleshooting of any digital system.
We start by introducing some underlying concepts that are a vital part of digital technology; these concepts will expanded on as they are needed later in the book. We also introduce some of the terminology that is necessary when embarking on a new field of study, and add to it in every chapter. A complete glossary of terminology is presented in Appendix I.