The name is transistor derived from ‘transfer resistors’ indicating a solid state Semiconductor device. In addition to conductor and insulators, there is a third class of material that exhibits proportion of both. Under some conditions, it acts as an insulator, and under other conditions it’s a conductor. This phenomenon is called Semi-conducting and allows a variable control over electron flow. So, the transistor is semi conductor device used in electronics for amplitude. Transistor has three terminals, one is the collector, one is the base and other is the emitter, (each lead must be connected in the circuit correctly and only then the transistor will function). Electrons are emitted via one terminal and collected on another terminal, while the third terminal acts as a control element. Each transistor has a number marked on its body. Every number has its own specifications.
There are mainly two types of transistor (i) NPN & (ii) PNP
When a positive voltage is applied to the base, the transistor begins to conduct by allowing current to flow through the collector to emitter circuit. The relatively small current flowing through the base circuit causes a much greater current to pass through the emitter / collector circuit. The phenomenon is called current gain and it is measure in beta. PNP Transistor:
It also does exactly same thing as above except that it has a negative voltage on its collector and a positive voltage on its emitter.
Transistor is a combination of semi-conductor elements allowing a controlled current flow. Germanium and Silicon is the two semi-conductor elements used for making it. There are two types of transistors such as POINT CONTACT and JUNCTION TRANSISTORS. Point contact construction is defective so is now out of use. Junction triode transistors are in many respects analogous to triode electron tube.
A junction transistor can function as an amplifier or oscillator...
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