Transistors

Electronic transistor

Transistor

A transistor is a basic semiconductor element that consists of three terminals and three series-connected areas with different doping that determines the transition of the transistor (PNP or NPN). Its main task is amplification, switching and conversion of electrical signals and part of all modern electrical devices.

Transistors are made from a wafer of germanium or silicon and are not used alone, but usually in combination with integrated circuits. Their main task is to perform the role of an electronic switch that opens /stops/ and closes /starts/ an electric circuit according to a weak control signal, to switch weak circuits in microprocessors and integrated circuits. Also to amplify a weak signal, without its application, modern technologies such as radio, television, audio/video recordings, computers, telephones, the Internet would no longer work.

Types of transistor

 

• Bipolar transistors
• FET transistors

Bipolar transistors

The most important feature of bipolar transistors is that they have an injection of current carriers through the PN junction and their operating current is determined simultaneously by two types of current carriers, hence the name bipolar.

FET transistors

For field-effect transistors, there is no injection of current carriers through the junction and their operating current is determined by either only electrons or only holes, therefore, field-effect transistors are also called unipolar.

Transistors have a huge practical application and are active elements in almost all modern electronic devices. They are often used assembled into integrated circuits and chips. Transistors are also widely used in the production of inverter welding and power supply devices.

Transistor Functionality

In general, the method of operation of a transistor is based on its ability to change a voltage or current pulse passed through one pair of terminals. The output voltage or current through another pair of terminals is higher or lower, respectively.