What is Electronics?


Electronics is a branch of science and engineering discipline that is concerned with the study of the behavior, emission and control of flow of electrons and their uses in vacuums, gases, and semiconductors. The term originally was applied to the study of electron behavior and movement, particularly as observed in the first electron tubes. Electrons are manipulated to achieve a desired result, and this is accomplished by different electronic components such as transistors, diodes, and integrated circuits to control and amplify the flow of electric current. Components are designed and manufactured in a specific manner so that they can select, resist, switch, carry, store electrons and other electrically charged particles. Electronics use active devices to control electron flow by amplification and rectification.


Electronics distinguishes itself from classical electrical engineering. The advancement in the field of electronics began with advances in knowledge about the fundamental nature of electrons and about the way in which the motion of these particles could be utilized. Today many scientific and technical disciplines deal with different aspects of electronics. Electronics deals with the development and application of many devices and systems that are in use in day-to-day life. Design, creation, and use of electronic devices is involved in electronics. It ranges from billions of nano-sized transistors in a single computer chip which cannot be seen from the naked eyes to as big as very large transformers and electrical outputs.

History of Electronics

Electronics has hugely affected the development of modern society after the identification of the electron in 1897.

Invention of Vacuum Tubes- The history of electronics began with the invention of vacuum tube by the father of electronics sir John Ambrose Fleming (29 November 1849 – 18 April 1945). An English electrical engineer and physicist who invented the first thermionic valve or vacuum tube. The simplest vacuum tube (i.e. Fleming valve), invented in 1904. It could amplify and rectify small electrical signals.


Above image is the first prototype of Fleming valves, built October 1904. Vacuum tubes or thermionic valves were the first electronics active electronics components. These tubes were used in the construction of radio, television, radar, long-distance telephone and much more.

Invention of Transistor-Another big invention in human history and the history of electronics was the invention of the transistor. John Bardeen and Walter Houser Brattain invented the world's first working transistor in 1947 at Bell Labs.




In April 1955, the IBM 608 was the first IBM product to use transistor circuits without any vacuum tubes and is believed to be the first all-transistorized calculator to be manufactured for the commercial market. It contained more than 3,000 germanium transistors. At that time the junction transistor was very bulky and hard to manufacture on mass scale, so the applications of these transistors were limited. MOSFET stands for metal oxide semiconductor field effect transistor. It was the first truly compact transistor that could be miniaturized and mass-produced for a wide range of uses. MOSFET revolutionized the electronics industry, becoming the most widely used electronic device in the world.

Invention of Integrated circuits (ICs)- After the invention of integrated circuits in electronics everything changed. The Geoffrey Dummer, English electronics engineer and consultant who talked about integrated circuits for the first time in 1952. He presents his conceptual work in Washington DC in a conference. He is also called prophet of the integrated circuit.

Robert Noyce invented the first monolithic integrated circuit in 1959. Below image is the image of Robert Noyce.




The chip was made from silicon. On April 25, 1961, the patent office awarded the first patent for an integrated circuit to Robert Noyce. The invention of ICs was a major leap in the history of technology. Now we see integrated circuits in all printed circuit boards. ICs have three main advantages compared to a dedicate circuits: size of the ICs is small so the circuit can be compact, cost of ICs is less, and ICs give better performance.

Different sub-fields of electronics are as following-
Analog electronics
Microelectronics
Nanoelectronics
Optoelectronics
Power electronics
Semiconductor devices
Telecommunications
Audio electronics
Bioelectronics
Circuit design
Digital electronics
Embedded systems
Integrated circuits

Electronics Components

An electronic component is a part used in a circuit to get done a specific task. Different electronic components work with different laws of physics and have different tendencies. Different components work in different ways.


A component forces the electrons to flow in a specific direction, for a required time, force the electrons to lose their bonds, create electric fields etc.

There are two types of electronic components used in electronics
Active
Passive

Active electronic components- Active electronic components- Active electronics components are classified into two sub- categories. Tube electronic components and semiconductor components. Tube devices and components have been replaced by semiconductor components. An active electronic component used in amplifying, rectifying, or converting supplied electric energy. Active components require an external power source to work i.e. transistor, SCR (semiconductor active components). For example, a transistor has three terminals or legs i.e. emitter, base and collector. The emitter and collector are connected to the main voltage source of circuit, but base is connected to an external voltage source. The voltage difference between the base and the emitter should be at least 0.7V to turn on the transistor. 0.7v is provided from external voltage source.

Passive electronic component- A passive component consumes, stores, or releases supplied electric energy. It does not require an external power supply to work i.e. resistor, capacitor, inductor etc.

Printed Circuit Board

Printed circuit board is a non-conducting material board on which a circuit is printed. After a circuit is designed it is printed on PCB (printed circuit board). Buses (conducting copper wires or traces) printed on it to print a circuit. After that components used in that circuit are mounted or soldered on the board via soldering iron.


Components can be mount by the through-hole method (create a hole in the board to insert component legs in hole) or surface mount method. In the surface mount component is mounted on board’s surface without a hole made on it. PCBs are made of plastic or glass-fiber and resin composites and use copper traces, but a wide variety of other materials can be used. PCBs are rigid and can be made flexible as well and easily to fit in difficult places.

Applications of Electronics

Electronics have a huge impact on various aspects of modern life, society and culture as well as huge contribution to different fields such as communication, space exploration, entertainment, education, health care, industry, and security.

Elevated the growth of technology-Electronics have a huge impact on the overall development of modern world technology, and it would not be wrong to say that electronics is the backbone of today’s technology we see around us in form of calculators, digital watches, mobile phones, laptops, and computers etc.

Medical Applications-Electronics engineering has a huge impact on the health care sector in the form of a new sub field of electronics known as medical electronics. Engineers built machines like ECG (electrocardiogram), X-ray machine, MRI (Magnetic resonance imaging) and other very helpful gadgets to help patients as well as these gadgets also release excess burden of work for the doctors.

Industrial Applications-Electronics has its presence in automobile industry in digital infotainment system and microprocessors or chips, integrated circuits used in the self-drive cars like tesla. Amplifier circuits are used in industries to amplify low signals. Controls applications like movement of conveyor belt, automatic door openers, safety system, power control system.

Agriculture Applications-Agriculture has also revolutionized with applications of electronics in past few decades because of continuous development in IoT (internet of things) and remote monitoring of the crops. For example, farmers can put a soil moisture sensor in their fields, which would connect to the IoT system designed for remote crop monitoring. They get notified on their mobile devices whenever the soil moisture goes below the required water level for crops.

Entertainment-People entertain themselves on T.V., smartphones for watching movies and shows, using iPod, speakers to enjoy music, use projectors, VR (virtual reality) etc. All these devices and gadgets are electronic devices being used today.

Security and Military Defense Use-Electronics have applications in military defense. For example, RADAR (radio detection and ranging) is used in the military to detect enemies or objects nearby. Electromagnetic pulses are continuously transmitting via transmitter at 360 degrees. Distance and velocity of the object, which is moving, or static is calculated when electromagnetic pulses are reflected after striking the unknown object in some time. RADAR can detect the exact location of planes in sky and tanks on land. And the process is controlled by electronic circuits.

Electronic Instruments- Electronic measuring instruments are widely used in engineering and industrial areas for example Voltmeter to measure voltage Ammeter to measure current Digital oscilloscope to observe current waveforms Digital weighing machine to measure the exact weight of an object Digital clock for timers, digital speedometer etc.

Space Exploration Applications-Electronic circuits are used in any space application they play a significant role in creating efficient and reliable space systems.