A bipolar junction transistor (BJT) is commonly used as an amplifier or switch in electronic circuits. As a three-terminal device, it has an input stage and an output stage. At the input stage, the VI characteristics of a transistor are similar to the forward-bias characteristics of a signal diode. The transistor turns on (i.e., begins…
What are the different bipolar junction transistor configurations?
In A guide to bipolar junction transistors, the definition and types of transistors and their applications are covered. In What to look for in a BJT transistor datasheet, transistor specifications are discussed, including what’s required before using or choosing a transistor in a circuit. In this article, we’ll explain what transistor configurations are and why…
What to look for in a BJT transistor datasheet
In a previous article, we discussed the fundamental concepts of a bipolar junction transistor (BJT), which are the building blocks of electronics. We covered the two types of BJTs—NPN and PNP—including their construction, I-V characteristics, circuit configurations, applications, and types. Typically, transistors are used in a circuit or a circuit stage as a switch or an amplifier.…
A guide to bipolar junction transistors
The term transistor is derived from the words “transfer and “resistor.” The first semiconductor transistor was invented to replace the triode as an amplifier device, a vacuum tube with three electrodes. The transistor was smaller, lighter, and cheaper than a vacuum tube triode. It also proved easy to construct and had no heat losses like…