Transistors

Our brains & spinal cords are made up of many cells including neurons & glial cells, Neurons are cells that send & receive electrochemical signals to & from the brain & nervous system

There are about 100 billion neurons in the brain

In an electronic vision, it`s a tiny switch that let you think & remember things.

Computers have billions of transistors made from silicon,

Transistors have revolutionized electronics, they are getting smaller according to Moore`s law

As they are getting smaller, computers and electronics at all getting smaller

As they are getting smaller, computers and electronics at all getting smaller

Chemical engineers used silicon characteristics to control it as they want,

         -Make it act as a conductor.

         -Make it act as an insulator.

Simply they used a chemical process called Doping, which is intentionally introducing impurities into an extremely pure semiconductor to change its electrical properties

Now there are many different types of transistors

The main function of transistors that it can amplify & switch electrical power & electronic signals.

There are two main uses of transistors,

Transistors as an amplifier: which can amplify the input signal. 

Transistors as a switch: which can allow and stop the signal to pass represented as 0s and 1s making logic gates that are the brains of our computers.

Definition:

  A transistor is a semiconductor device used to amplify or switch electronic signal and electric power.
it`s composed of semiconductor material usually with at least three terminals for connection to an external circuit
when a voltage or current (depending on the type) applied to one pair of the transistor`s terminals controls the current
through another pair of terminals, because the controlled output power can be higher than the controlling input power,
a transistor has two main functions act as a switch or as an amplifier.
today some transistors are packaged individually, but many more are found embedded in integrated circuits(ICs)

there are three common types of transistors used in our circuits:

Bipolar junction transistor [ BJT ]:

A bipolar junction transistor is a type of transistor that uses both electron and hole charge carriers. In contrast,
unipolar transistors, such as field-effect transistors, only use one kind of charge carrier.

Metal oxide semiconductor field effect transistor [ MOSFET ]:

The metal-oxide-semiconductor-field-effect transistor is a type of field-effect transistor, most commonly fabricated by the controlled oxidation of silicon. It has an insulated gate, whose voltage determines the conductivity of the device.

Insulted gate bipolar transistor [ IGBT ]:

An insulated-gate bipolar transistor (IGBT) is a three-terminal power semiconductor device
primarily used as an electronic switch which, as it was developed, came to combine high efficiency
and fast switching.

Transistor Tree: