Designing Embedded Hardware

Chapter 2. Electronics 101

. . . in reality, nothing but atoms and void

—Democritus

In writing this book, my hope is to bring to you an understanding of the design process involved in producing an embedded computer system. To this end, I have kept the electronics, the chips, and the systems I have used as simple as possible. I want you to understand the big picture without getting lost in the details. But, no matter how simple I keep the computer designs, you won’t get very far without at least a very rudimentary understanding of electronics. So this chapter presents basic background theory to guide you on your way. Electronics is a truly vast and complex multidisciplinary field, and it is not possible to cover even a thousandth of it in a single chapter. What I will do is to give you an easy-to-understand grounding in the basic principles necessary for embedded computer engineering. The rest of the vast mountain I will leave unvisited. If you want to learn more, pick up a copy of Paul Horowitz and Winfield Hill’s The Art of Electronics, published by Cambridge University Press. It’s a great introductory text. For some fun, interactive online tutorials go to http://www.clarkson.edu/~svoboda/eta.

Voltage and Current

It’s all about electrons— hence the term, “electronics.” Electrons are subatomic particles with a negative charge. They are bound to positively charged atomic nuclei through Coulombic attraction. The classical physics view was to think of electrons “orbiting” the nucleus, ...