Electronics For Dummies, 3rd Edition

Chapter 9

Diving into Diodes

IN THIS CHAPTER

Peeking inside a semiconductor

Fusing two semiconductors to make a diode

Letting current flow this way but not that way

Semiconductors are at the heart of nearly every major electronic system that exists today, from the programmable pacemaker to your smartphone to the space shuttle. It’s amazing to think that teeny-tiny semiconductor devices are responsible for triggering enormous advances in modern medicine, space exploration, industrial automation, home entertainment systems, communications, and a slew of other industries.

The simplest type of semiconductor device, called a diode, can be made to conduct or block electric current and to allow current to flow in one direction but not the other — depending on how you control it electrically.

This chapter explains what semiconductors are, how to make them conduct current, and how to combine two semiconductors to create a diode. Then you get an eyewitness view of the valve-like behavior of diodes — and take a look at how to exploit that behavior to accomplish amazing things in circuits.

Are We Conducting or Aren’t We?

Somewhere between insulators and conductors are materials that can’t ...