## Introduction

The transistor is an electronic piece consisting of semi-conductive materials with three legs; the semiconductor material on the limbs is similar, screen varies in the middle. We consider it one of the most critical inventions in electronics, replacing large-scale vacuum valves.

Bipolar junction Transistor is divided into PNP and NPN, which are most widely used. The TRANSISTOR HAS THREE PARTIES: BASE B, POOL C, AND E EMITTER. The emitter is a side end on which carbonate charges are concentrated. Generating electrons, generating electricity, and symbolizing it with an E

Base: It is the average tip between the radiator and the compound and controls the direction and quantity of the electric current and symbolizes it with a letter (B). * Collector: This is another side end; unlike the emitter. It is less concentrated for electrical charges, which in turn collect the following current from the emitter and its symbol (E).

## Transistor Uses

Transistor as critical the mechanical key separates the current from the circle. Thus extinguishing the circuit or device if we take the example of a simple electrical course consisting of a source of voltage, connected to resistance.

And resistance related to a key to the inheritance or ground, when the key is open the voltage on both sides of the opposition is equal to the voltage of the source, i.e., there is no voltage. So the current does not apply. Still, if we close the key. The voltage on the resistance end connected to the key becomes zero, i.e., it forms an effort difference around the voltage on both sides of the resistance, the current goes on.

In the same principle, the transistor works; when the current at the base (Ib) is equal to zero, the transistor becomes a high resistance, preventing the passage of the current through it. Forming an open circle does not constitute an effort difference.

The transistor acts as an available key. But when the current saturation phase (Isat). A stream passes from the complex to the emitter connected to the ground. Works to join the circle, forming an effort between the sides of the resistance and the left of the current. Thus the transistor acts as a closed key.

The values necessary for the circle can be calculated theoretically by relying On the following equations: V(Rc)=Ice*Rc V(Rc)+V(ce)=Vcc where: Vic: Is the voltage difference between the two sides of the resistance connected to the complex. Ice: The combined and emitting primary current. Vce: The voltage difference between the compound and the emitter.

## Another Transistor

There are many other uses of the transistor, an essential component of electrical circuits and electronics: the electromagnetic wave or signal grows and is called an amplifier. It reflects electrical signals. We use it as a signal oscillator in high-frequency circuits. Integrating the movement into the reception circles is called the channel team—integrate signs in vertical deviation circles.

Emitter: It is one of the edges of the crystals. Not the middle crystal and we distinguish in the symbol from the arrow, where the needle is always on that end in the electric character and symbolizes it with nature (E).

Collector: The other end of the crystals, not the center crystal, symbolizes it (C).

Base: The middle end between the two crystals. Which is of a different type to other crystals, and is coded (B). We must note an electronic piece consisting only of two crystals called a diode, i.e., it is formed from a negative crystal and a positive crystal.

And the diode connects the electric current in only one direction and acts as an insulator in the opposite direction.

From the above, We found that if it enters a hesitant effort. It leaves the current running at half the voltage cycle. Preventing the current from running in the other half process. And thus acts as a component. That is, it converts the ac into a continuous current. This means that it is on, and the cathode is the positive end, and the anode is the opposing party.