Which best describes a p-type semiconductor?

Upon completion of this chapter, you should be able to do the following:

Define the term transistor and give a brief description of its construction and operation.

• Explain how the transistor can be used to amplify a signal.
• Name the four classes of amplifiers and give an explanation for each.
• List the three different transistor circuit configurations and explain their operation.
• Identify the different types of transistors by their symbology and alphanumerical designations.
• List the precautions to be taken when working with transistors and describe ways to test them.
• Explain the meaning of the expression "integrated circuits."
• Give a brief description on how integrated circuits are constructed and the advantages they offer over conventional transistor circuits.
• Name the two types of circuit boards.
• State the purpose and function of modular circuitry.

INTRODUCTION TO TRANSISTORS

The discovery of the first transistor in 1948 by a team of physicists at the Bell Telephone Laboratories sparked an interest in solid-state research that spread rapidly. The transistor, which began as a simple laboratory oddity, was rapidly developed into a semiconductor device of major importance. The transistor demonstrated for the first time in history that amplification in solids was possible. Before the transistor, amplification was achieved only with electron tubes. Transistors now perform numerous electronic tasks with new and improved transistor designs being continually put on the market. In many cases, transistors are more desirable than tubes because they are small, rugged, require no filament power, and operate at low voltages with comparatively high efficiency. The development of a family of transistors has even made possible the miniaturization of electronic circuits. Figure 2-1 shows a sample of the many different types of transistors you may encounter when working with electronic equipment.