Physics

Development of Electronics

The present era is the era of electronics. Radio, television, phone, fax, camera, computer, watch etc. are the contributions of electronics. The control of the electric current through a vacuum tube, the special type of crystals and chips is known as electronics. The history of electronics is ancient of more than hundred years. The real journey of electronics begins with the invention of Addison’s effect in 1883. When Addison was working with the electric lamp, one thing was disturbing him highly. The positive end of the filament of carbon of the lamp was burning again and again. To remove this difficulty, he entered a plate by sealing it with the filament. He saw that when a positive potential is given to the plate with respect to the filament, an electric current flows through the vacuum tube. But when a negative potential is applied to the plate electric current does not flow.

Addison explains this phenomenon in this way- as the emitted charge from the hot filament goes to the positive plate, so this charge is negative. If the plate is negative, it repels the emitted charge, as a result, no current flows through the circuit. This is known as Addison effect. British physicist Fleming first invented the vacuum tube by using Addison effect. This tube works as a rectifier that means it changes alternating current to direct current. This is the real beginning of electronics. During this time, a detector was very necessary for Marconi’s Radio. This tube fills up the need of the detector. As there were two electrodes in it, this is called a diode. After two years, an American named Lee de Forest invented another vacuum tube called triode.

Since it had three electrodes, it was named as a triode. Besides anode and cathode, there was another electrode known as a grid in it. Grid controls the flow of electric current from anode to cathode. It is wonderful that the triode can work as an amplifier. So triode plays a vital role in the development of communication.

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As the size of diode and triode valves are very large, they create problem to fix them in different electronic devices. The expense of power for it is more, it is less reliable and cooling system is necessary to keep it cool. So the scientists were searching for a semiconductor device as its alternative. Later they invented p-n junction diode. After long experiments, they were able to invent n-p-n transistor. Transistor works as an amplifier.

To set up several components in a single motherboard, problem creates. Sometimes it becomes impossible. So, IC or integrated circuit is invented. IC is such a creation using semiconductors like silicon, where millions of microscopic electric circuits are gathered in a place like a nail of our finger. Revolutionary changes took place in the design of IC chips after its invention in 1960.