Question

assignment on transistor

Answer 1

A transistor is a device which is used to amplify electronic signal and electrical power. It can switch the signal and power. It is a semiconductor device. The transistor was little in size but it was a very powerful invention that changed the history, great way for computers and electronics. With use of transistor we can change the voltage and current applied to the circuit. When we will give current or voltage to one pair of transistor terminals, it changes the current flowing by another pair of transistor terminals. Because of that the output of a transistor can be higher than its input.

A transistor has a function of amplify the signal. In many electronics component transistor can be use as a switch. Transistors are used in a circuit. It is very rare to find that a circuit can built without transistor.

They are mainly two types which are NPN and PNP.most circuits are used NPN transistor. There are many types of transistor which are work at different inputs but all of them are part of these two categories. Transistor is a little invention that can make great changes.

The transistor is a primary and essential building block of modern electronics device. The transistor present every where simultaneously in modern electronic system. The transistor is the similar implementation for operating a switch component in all modern electronics. It is a very greatest invention of 20th century. Today in electronic world transistor’s demand is very high. It’s over a billion. Discrete transistors are produced by many companies. The huge part of transistor is produced in integrated circuit in addition to diodes, resistors, capacitors and distinct in kind electronic component.

A logics gate is a composition of twenty transistors. The transistors are very cheap in cost and it is very flexible and reliable to make a device. Because of its characteristics it is present everywhere .it can control a much larger signal at one pair of terminal by applying small signal at another pair of its terminal. This property of transistor is called gain. It is also used as an amplifier.

Transistors are small in size and have very minimal weight because of these we can develop a very small size electronics device. Its manufacturing process is very low in cost and very highly automated. It can operate at very low voltage so that transistor is suitable for making very small application.

It has high reliability and physical uneven .its life is extremely long. It can give service for more than 50 years. Silicon transistors can not operate at higher than 1000 volts but vacuum tubes can be operated at more than 1000 volts and up to 10000 volts.

Transistors have many different shapes but all have three legs. Legs are also called leads which are the base, the collector and the emitter. The base leg is used for activating the transistor. The collector leg is a positive lead. The emitter leg is a negative lead-in a switch circuit we use NPN transistor.
There is a resistor to protect the transistor .it can be damaged by too high voltage/current. There are many types of transistor like bipolar junction transistor, field effect transistors etc.

Types of bipolar transistors:

Avalanche transistor, Darlington transistor, schottky transistor, photo transistor, multiple emitter transistors.

Types of field effect transistor:

Thin film transistor, ballistic transistor, inverted -T field effect transistor, FLOATING GATE TRANSISTOR, JFET, MESFET, MOSFET.

Answer 2

By turning a small input current into a large output current, the transistor acts like an amplifier. But it also acts like a switch at the same time. When there is no current to the base, little or no current flows between the collector and the emitter. Turn on the base current and a big current flows