Electronics All-in-One For Dummies, 3rd Edition

Chapter 5

Working with Diodes and LEDs

IN THIS CHAPTER

Digging deep into how semiconductors work

Looking at the simplest of semiconductors, the lowly diode

Understanding how diodes can change AC to DC

Seeing how some diodes can make light

So far in this book, all the components I tell you about were invented in the first 100 years or so since Alessandro Volta invented the first electric battery in 1800. The next 50 years of electronics, from roughly 1900 to 1950, were dominated by a technology that’s now all but obsolete: vacuum tubes, which were large, expensive, fragile (they were made of glass), and required a lot of current.

In the 1940s, researchers developed a new technology that lead to new components that were, literally, a quantum-leap improvement over vacuum tubes. These new components were called semiconductors.

This chapter introduces you to the most basic kind of semiconductor, called a diode. Diodes come in many shapes and sizes, but most of them resemble the ones shown in Figure 5-1. These diodes are about the size of resistors and are available from any electronics ...