WHAT IS ELECTRONICS?

It is the branch of physics concerned  with the emission and effects of electrons and the working of electronic devices or electronic materials.

Electronics is the study of the flow of charge through various materials such as, semiconductors, resistors, inductors, capacitors and vacuum tubes. Every usage of electronics involve the transmission of either the information or power. The design and construction of electronic circuits to solve practical problems is an essential technique in the fields of electronics engineering.

The study of new semiconductor devices and surrounding technology is sometimes considered a branch of physics.

The concept of electronics is used about electronic components, integrated circuits and electronic systems. Few years back, no one had ever thought of the expansive growth of the electronics-, information- and communication technology we have seen the last decades. Our new digital life is built on the development of miniaturized electronic circuits (microchips) and broadband telephone- and data transmission through optical fiber and wireless networks.

No one now has been left untouched or unaware of electronics .It plays a vital part in everyone's life. 

Computers has been a common tool both at work and at home. The PC(Personal computers)and other advanced electronics have been commercially available for all people in general. The capacity of the computers almost doubles every year. This expansion is achievable because of tighter packaging of the components onto the microchip. But as we get closer to the atomic limit where each component on the microchip is just a few atom lengths, we need innovative developments for the future.

Analog electronics

Analog electronics was used in large part because of the ease with which circuits could be implemented with analog devices. However, as signals have become more complicated, and the ability to fabricate extremely complex digital circuits has increased, the disadvantages of analog electronics have increased in importance, while the importance of simplicity has declined.

In analog electronics, the signals to be manipulated take the form of continuous currents or voltages. The information in the signal is carried by the value of the current or voltage at a particular time t. Some examples of analog electronic signals are amplitude-modulated (AM) and frequency-modulated (FM) radio broadcast signals, thermocouple temperature data signals, and standard audio cassette recording signals. In each of these cases, analog electronic devices and circuits can be used to render the signals intelligible.

Commonly required manipulations include amplification, rectification, and conversion to a nonelectronic signal. Amplification is required when the strength of a signal of interest is not sufficient to perform the task that the signal is required to do. However, the amplification process suffers from the two primary disadvantages of analog electronics: (1) susceptibility to replication errors due to nonlinearities in the amplification process and (2) susceptibility to signal degradation due to the addition, during the amplification process, of noise originating from the analog devices composing the amplifier. These two disadvantages compete with the primary advantage of analog electronics, the ease of implementing any desired electronic signal manipulation. See also Amplifier; Distortion (electronic circuits); Electrical noise.

Digital electronics

It includes flip flops ,transistors working etc. It is a branch of electronics in which we use binary numbers 0 and 1.The advent of the transistor in the 1940s made it possible to design simple, inexpensive digital electronic circuits and initiated the explosive growth of digital electronics

Some electronic terms which we should know

Alternating (AC) Current - currents that have a harmonic time dependence.

Ampere (A) - the unit of measurement for electrical current in coulombs per second.

Amplifier - an electrical circuit designed to increase the current or voltage of an applied signal.

Amplitude - the relative magnitude of a signal.

Baffle - a board or other planar surface used to mount a loudspeaker.

Bandwidth - the range of frequencies reproduced by an amplifier or transducer

Bi-amping - an extension of bi-wiring in that a separate amplifier is utilized for each of the two sets of connectors from the cross-over.

Bipole -- A speaker design which generates equal amounts of sound both forward and backward, with the two sounds being "in phase". See also Dipole

Capacitor - a charge storage device made up of two metallic plates separated by a dielectric, with equal but opposite charges. The AC impedance of a Capacitor is (1 / jWL) and acts as an open circuit in DC applications.

Circuit - a complete path that allows electrical current from one terminal of a voltage source to the other terminal.

Class A - transistor amp conducts for the entire cycle of input signal, conduction angle 360 deg. Runs hot, as the transistors in the power amp are on all the time, but has high sound quality.

Class B - positive and negative halves of the signal dealt with by different parts of the circuit, the output devices switching continually. Runs cooler, but the sound is not as pure.

Class AB - biasing the transistor amp at a non-zero DC current much smaller than the peek current of the signal source. Second transistor conducts during negative half cycle of waveform and the currents from the 2 transistors are combined at the load. A compromise between sound quality of Class A and efficiency of Class B. Most amp designs employ this method.

Damping - the reduction of movement of a speaker cone, due either to the electromechanical characteristics of the speaker driver and suspension, the effects of frictional losses inside a speaker enclosure, and/or by electrical means.

Damping Factor - This is a quantity which defines how quickly the amplifier can stop a reproduced frequency such as a bass note. The higher the damping factor, the better the amp will control the woofer and help reduce overhang distortion. The damping factor of an amplifier is mostly dependent on the quality of the power supply which feeds the power amp

Diffusion - The scattering of sound.

Dipole - A speaker design which generates equal amounts of sound both forward and backward, with the two sounds being out of phase. Dipoles are often used as surround speakers. See also Bipole.

Direct Current (DC) - current in only one direction.

Diffraction - a change in the direction of a wave that is caused by the wave moving past or hitting an obstacle.

Dispersion - the spreading of sound waves as it leaves a speaker.

Distortion - any undesirable change or error in the reproduction of sound that alters the original signal.

Frequency - the number of waves (or cycles) arriving at or passing a point in one second, expressed in hertz (Hz).Hertz (Hz) - a measurement of the frequency of sound vibration. One hertz is equal to one cycle per second. The hertz is named for H.R. Hertz, a German physicist

Impedance - dependent on frequency, it is the AC equivalent of resistance in a DC circuit.

Inductance (L) - the capability of a coil to store energy in a magnetic field surrounding it. It produces an impedance to an AC current (jwL) and acts as a short circuit to DC. Inductors are commonly used in audio as low pass crossovers

Ohm - a unit of electrical resistance or impedance.

Ohm's Law - a basic law of electric circuits. It states that: the current [I] in amperes in a circuit is equal to the voltage [V] in volts divided by the resistance [R] in ohms; thus, I = V/R.

Volt (E) - a unit of measurement used to measure how much "pressure" is used to force electricity through a circuit.

Watt - a unit of electrical power. A watt of electrical power is the use of one joule of energy per second. Watts of electrical power equals volts times amperes.

Wavelength - the length of a sound wave in air. It can be found for any frequency by dividing the speed of sound in air (1120 feet per second) by the frequency of the sound, or: WL = 1120 / Freq

What is Nanoelectronics?

Nanoelectronics refer to the use of nanotechnology on electronic devices. The term nanotechnology is generally defined as utilizing technology less than 100nm in size, nanoelectronics often refer to transistor devices that are very small. Nanoelectronics are sometimes considered as disruptive technology because present candidates are significantly different from traditional transistors. Some of these candidates include: hybrid molecular/semiconductor electronics, one dimensional nanotubes/nanowires, or advanced molecular electronics.

What is Spintronics?

It is also known as magnetoelectronics, is an emergent technology which exploits the quantum spin states of electrons as well as making use of their charge state.