How does Transistor Work

 The transistor is a semiconductor device for amplifying, controlling, and generating electrical signals. Transistors are the active components of integrated circuits that containing billions of minuscule devices etched into the surface. It is used as an amplifier or switches electronic signals and electrical power. Transistors are one of the basic building blocks of modern electronics. the word transistor is made of the two words, transfer and resistance. This is because it has the function of transferring the resistance from one end of the device to the other end or we can say, transfer of resistance. Transistors have very high input resistance and very low output resistance. 

It is composed of semiconductor material usually with at least three terminals for connection to an external circuit. It works when the holes start moving across the two junctions between the n-type and p-type silicon. When turning a small input current into a large output current, the transistor acts as an amplifier. But it also acts as a switch at the same time when this happens.

A transistor consists of two diodes connected back to back. It has three terminals namely emitter, base, and collector. The basic idea behind a transistor is that it lets you control the flow of current through one channel of a much smaller current that's flowing through a second channel. 

There are two types of transistors. One is BJT and the other is FET.

The primary transistor is the BJT and get is the modern version of the transistor. The types of BJT are NPN and PNP transistors. In an NPN transistor, a positive voltage is given to the collector terminal to produce a current flow from the collector to the emitter. In a PNP transistor, a positive voltage is given to the emitter terminal to produce current flow from the emitter to the collector. The FET is quite an unknown device in this modern time. The device means that it is made using either p-type or n-type material as the main substrate. 

Transistors are used in our day-to-day lives in many forms. As amplifiers, they are being used in various detectors, and nearly in any circuit in order to perform a function. In digital circuits, transistors are used as switches. Transistors make excellent electronic switches. They can turn currents on and off super fast. Digital computers use transistors as a basic mechanism for storing and moving data. 

Transistors are also found in hearing aids, cameras, calculators, and watches. most of these devices draw their power from tiny batteries. most spacecraft also rely on microchips, and thus transistors. The transistor is called the nerve cell of the information age.

To know more: What does usually a transistor do?

Reference: https://en.wikipedia.org/wiki/Transistor_(disambiguation)