How Dose a Transistor Work?Transistor DefinitionA transistor is defined as a semiconductor device used to amplify or switch electronic signals.There are different types of transistors available, but we’ll focus on the NPN transistor in common emitter mode. This type has a heavily doped and wide emitter region, which contains many free electrons (majority carriers). The collector region is wide and moderately doped, so it has fewer free electrons than the emitter. The base region is very thin and