ABSTRACT
This chapter explains the structure and operation of the transistor, incorporating some simple calculations. It aims to understand the structure of bipolar junction transistors (BJT) and junction gate field effect transistors (JFET). The chapter describes different classes and applications for BJT and JFET devices. It presents how transistors are used as Class-A amplifiers. The invention of the bipolar transistor in 1948 started arevolution in electronics. JFETs offer a very much higher input resistance when compared with bipolar transistors. A transistor is a three-terminal semiconductor device that can perform two functions that are fundamental to the design of electronic circuits – amplification and switching. Transistors can be mass produced at very low costs, and transistors are the reason that computers keep getting smaller yet more powerful every day. Silicon transistors are superior when compared with germanium transistors in the vast majority of applications and thus germanium devices are very rarely encounteredin modernelectronic equipment.
