construction work started in and got over in . It occupied an area of around square feet. It had , vacuum tubes and it weighed around tons. The following years witnessed the invention of the integrated circuits (ICs) that helped to integrate the entire electronic circuit on a single chip which is small in size and cost-effective.
Since ICs capable of holding several thousand electronic components on a single chip such as small- scale, medium-scale, large-scale, and very- large scale integration started coming into existence. Digital integrated circuits became another robust IC development that enhanced the architecture of computers. All these radical changes led to the introduction of microprocessor in by Intel. The electronics revolution, in due course of time, accelerated the computer revolution .
Now the world is on its way towards small particles of nano-size, far too small to see. This helps in the miniaturization to an unimaginable size. A room-size computer during its invention has now emerged as a laptop, palmtop, iPad, etc. In the recent past, IBM has released the smallest computer whose size is comparable to the tip of the rice grain, measuring just .
mm on each side. Electronics is the branch of physics which incorporates technology to design electrical circuits using transistors and microchips. It depicts the behaviour and movement of electrons and holes in a semiconductor, electrons and ions in vacuum or gas. Electronics deals with electrical circuits that involve active components such as transistors, diodes, integrated circuits and sensors, associated with the passive components like resistors, inductors, capacitors and transformers.
This chapter deals with semiconductor devices like p-n junction diodes, bipolar junction transistors and logic circuits. - - - - - - - - Unit electronics and Communication energy levels will be closely spaced and will be difficult to differentiate the orbitals of one atom from the other and they look like a band as shown in Figure . . This band of very large number of closely spaced energy levels in a very small energy range is known as energy band.