capacitors

A capacitor (originally known as a condenser) is a passive two-terminalelectrical component used to temporarily store electrical energy in an electric field. The forms of practical capacitors vary widely, but most contain at least two electrical conductors (plates) separated by a dielectric (i.e. an insulatorthat can store energy by becoming polarized). The conductors can be thin films, foils or sintered beads of metal or conductive electrolyte, etc. The nonconducting dielectric acts to increase the capacitor's charge capacity. Materials commonly used as dielectrics include glass, ceramic, plastic film,paper, mica, and oxide layers. Capacitors are widely used as parts of electrical circuits in many common electrical devices. Unlike a resistor, an ideal capacitor does not dissipate energy. Instead, a capacitor stores energy in the form of anelectrostatic field between its plates.

Inductors

An inductor has been defined as a physical device which capable of storing energy by virtue of current flowing through it.
An indouctor is a circuit component 

results from the magnetic field around a current-carrying conductor; the electric current through the conductor creates a magnetic flux. Mathematically speaking, inductance is determined by how much magnetic flux φ through the circuit is created by a given current i^[1][2][3][4]

${\displaystyle L={\phi \over i}}$        (1)

Inductors that have ferromagnetic cores are nonlinear; the inductance changes with the current, in this more general case inductance is defined as

${\displaystyle L={d\phi \over di}\,}$

Constitutive equation[edit]

Any change in the current through an inductor creates a changing flux, inducing a voltage across the inductor. By Faraday's law of induction, the voltage induced by any change in magnetic flux through the circuit is

From (1) above^[4]

${\displaystyle v={d \over dt}(Li)=L{di \over dt}\,}$   

Types of inductor

1. Air Core Inductors
• In this type of inductor, core is completely absent. These inductors offer high reluctance path for the magnetic flux, hence less inductance. The air core inductors have larger coils to produce higher flux densities. These are used in high frequency applications including TV and radio receivers.
  
2.  Ferro Magnetic or Iron Core Inductors
• These are the different types of inductors which offer advantages of decreased cost and low core losses at high frequencies. Ferrite is a metal oxide ceramic based around a mixture of Ferric Oxide Fe2O3. Soft ferrites are used for the core construction to reduce the hysteresis losses.
  
3. Bobbin based Inductors
• In this type, coil is wounded on the bobbin. Bobbin wound inductor designs vary widely in terms of power rating, voltage and current levels, operating frequency, etc. These are mostly used in switch mode power supplies and power conversion applications.
  
4. Multi Layer Inductors
• A multilayer inductor contains two conductive coil patterns which are arranged in two layers in the upper part of a multi-layered body. The coils are connected electrically in a consecutive manner in series to two more conductive coil patterns disposed in the lower part of the multi-layered body. These are mainly used in mobile communication systems and noise suppression applications.
  
5. Thin Film Inductors


• These are completely different from the conventional chip-type inductors wound with copper wire. In this type, tiny inductors are formed using thin-film processing to create the chip inductor for high-frequency applications, which ranges from about nano Henry.
  

Resistor

Resistor Basics

Resistors are electronic components which have a specific, never-changing electrical resistance. The resistor’s resistance limits the flow of electrons through a circuit.

They are passive components, meaning they only consume power (and can’t generate it). Resistors are usually added to circuits where they complement active components like op-amps, micro controllers, and other integrated circuits. Commonly resistors are used to limit current, divide voltages, and pull-up I/O lines.

Resistor units

The electrical resistance of a resistor is measured in ohms. The symbol for an ohm is the Greek capital-omega: Ω. The (somewhat roundabout) definition of 1Ω is the resistance between two points where 1 volt (1V) of applied potential energy will push 1 ampere (1A) of current.

• Type Of Resistors 
1. carbon composition resistors  
   
2. Wirewond resistor
   
3.  Metal film and carbon film resistor
   

Componentes

All electronic circuits,how ever completed, contain a few basics components (generally speaking,only five).

There are two types of component.

1. Active   component
2. passive  component

• Active component
• Active components rely on a source of energy (usually from the DC circuit, which we have chosen to ignore) and usually can inject power into a circuit, though this is not part of the definition.^[1] [2]Active components include amplifying components such as transistors, triode vacuum tubes (valves), and tunnel diode.

• Passive component
• Passive components can't introduce net energy into the circuit. They also can't rely on a source of power, except for what is available from the (AC) circuit they are connected to. As a consequence they can't amplify (increase the power of a signal), although they may increase a voltage or current (such as is done by a transformer or resonant circuit). Passive components include two-terminal components such as resistors, capacitors, instructors, and transformers.

Brief History Of development of electronics

In this 21st century, every day we are dealing with the electronic circuits and devices in some or the other forms because gadgets, home appliances, computers, transport systems, cell phones, cameras, TV, etc. all have electronic components and devices. Today’s world of electronics has made deep inroads in several areas, such as healthcare, medical diagnosis, automobiles, industries, electronics projects etc. and convinced everyone that without electronics, it is really impossible to work.

Therefore, looking forward to know the past and about the brief history of electronics is necessary to revive our minds and to get inspired by those individuals who sacrificed their  lives by engaging themselves in such amazing discoveries and inventions that costs everything for them, but nothing for us, and, in turn, benefitted us immensely since then.

Brief history of electronics

Brief History of Electronics and Its Development

Electronics’ actual history began with the invention of vacuum diode by J.A. Fleming, in 1897; and, after that, a vacuum triode was implemented by Lee De Forest to amplify electrical signals. This led to the introduction of tetrode and pentode tubes that dominated the world until the World War II.

Subsequently, the transistor era began with the junction transistor invention in 1948. Even though, this particular invention got a Nobel Prize, yet it was later replaced with a bulky vacuum tube that would consume high power for its operation. The use of germanium and silicon semiconductor materials made theses transistor gain the popularity and wide-acceptance usage in different electronic circuits.

Integrated circuits (ICs)

The subsequent years witnessed the invention of the integrated circuits (ICs) that drastically changed the electronic circuits’ nature as the entire electronic circuit got integrated on a single chip, which resulted in low: cost, size and weight electronic devices. The years 1958 to 1975 marked the introduction of IC with enlarged capabilities of over several thousand components on a single chip such as small-scale integration, medium-large scale and very-large scale integration ICs.

And the trend further carried forward with the JFETS and MOSFETs that were developed during 1951 to 1958 by improving the device designing process and by making more reliable and powerful transistors.

Digital integrated circuits were yet another robust IC development that changed the overall architecture of computers. These ICs were developed with Transistor-transistor logic (TTL), integrated injection logic (I2L) and emitter coupled logic (ECL) technologies. Later these digital ICs employed PMOS, NMOS, and CMOS fabrication design technologies.

All these radical changes in all these components led to the introduction ofmicroprocessor in 1969 by Intel. Soon after, the analog integrated circuits were developed that introduced an operational amplifier for an analog signal processing. These analog circuits include analog multipliers, ADC and DAC converters and analog filters.

This is all about the fundamental understanding of the electronics history. This history of electronics technology costs greater investment of time, efforts and talent from the real heroes, some of them are described below.

Inventors in history of electronics

Luigi Galvani (1737-1798)

Luigi Galvani was a professor in the University of Bologna. He studied the effects of electricity on animals, especially on frogs. With the help of experiments, he showed the presence of electricity in frogs in the year 1791.

Charles Coulomb (1737-1806)

Charles coulomb was a great scientist of the 18th century. He experimented with the mechanical resistance and developed coulomb’s law of electro-static charges in the year 1799.

Allesandro Volta (1745-1827)

Allesandro Volta was an Italian scientist. He invented battery in the year 1799. He was the first to develop a battery (Voltaic cell) that could produce electricity as a result of chemical reaction.

Hans Christian Oersted (1777-1852)

Hans Christian Oersted showed that whenever a current flows through a conductor, a magnetic field is associated with it. He initiated the study of electromagnetism and discovered Aluminum in the year 1820.

George Simon Ohm (1789-1854)

George Simon Ohm was a German physicist. He experimented with the electrical circuitsand made his own part including the wire. He found that some conductors worked when compared to others. He discovered Ohms law in the year 1827, which is a relation between current, voltage& resistance. The unit for resistance is named after him.

Michael Faraday (1791-1867)

Michael Faraday was a British scientist and great pioneer experimenter in electricity and magnetism. After the discovery by Oersted, he demonstrated electromagnetic induction in the year 1831. This is the basic principle of the working of generators.

James Clerk Maxwell (1831-1879)

James Clerk Maxwell was a British physicist, and he wrote treatise on magnetism and electricity in the year 1873. He developed the electromagnetic field equations in the year 1864. The equations in it were explained and predicted by hertz’s work and faradays’ work. James Clerk Maxwell formulated an important theory – that is, electromagnetic theory of light.

Henrich Rudolph Hertz (1857-1894)

Henrich Rudolph Hertz was a German physicist born in 1857 in Hamburg. He demonstrated the electromagnetic radiation predicted by Maxwell. By using experimental procedures, he proved the theory by engineering instruments to transmit and receive radio pulses. He was the first person to demonstrate the photo-electric effect. The unit of frequency was named Hertz in his honorarium.

Andre Marie Ampere (1775-1836)

Andre Marie Ampere was a French mathematician and physicist. He studied the effects of electric current and invented solenoid. The SI unit of electric current (the Ampere) was named after him.

Karl Friedrich Gauss (1777-1855)

Karl Friedrich Gauss was a physical scientist and a greatest German mathematician. He contributed to many fields like algebra, analysis, statistics, electrostatics and astronomy. The CGS unit of magnetic field density was named after him.

Wilhelm Eduard Weber (1804-1891)

Wilhelm Eduard Weber was a German physicist. He investigated terrestrial magnetism with his friend Carl fried rich. He devised an electromagnetic telegraph in the year 1833, and also established a system of absolute electrical units, and the MKS unit of flux was named after Weber.

Thomas Alva Edison (1847-1932)

Thomas Alva Edison was a businessman and an American inventor. He developed many devices like, practical electric bulb, motion picture camera, photograph and other such things. While inventing the electric lamp, he observed the Edison effect.

Nikola Tesla (1856-1943)

Nikola Tesla invented the Tesla coil; the Tesla induction motor; alternating current (AC); electrical supply system that includes a transformer; 3-phase electricity and motor. In 1891, Tesla coil was invented and used in electronic equipment, television and radio sets. The unit of magnetic field density was named after him.

Gustav Robert Kirchhoff (1824-1887)

Gustav Robert Kirchhoff was a German physicist. He developed Kirchhoff’s law that allows calculation of the voltages, currents and resistance of electrical networks.

James Prescott Joule (1818-1889)

James Prescott Joule was a brewer and an English physicist. He discovered the law of conservation of energy. The unit of energy – Joule was named in his honor. To develop the scale of temperature, he worked with Lord Kelvin.

Joseph Henry (1799-1878)

Joseph Henry was an American scientist, and independently discovered electromagnetic induction in the year 1831 – a year before faraday’s discovery. The unit of induction was named after him.

Lee De Forest (1873-1961)

Lee de forest was an American inventor, and he invented the first triode vacuum tube: Audion tube in 1906. He was honored as the father of radio.

Walter schottky (1886-1997)

Walter schottky was a German physicist. He defined shot noise-random electron noise in thermionic tubes, and invented the multiple grid vacuum tube.

Edwin Howard Armstrong (1890-1954)

Edwin Howard Armstrong was an inventor and an American electrical engineer. He invented electronic oscillator and regenerative feedback. In 1917, he invented super-heterodyne radio and patented FM radio in the year 1933.

Hope you got somewhat better understanding of this brief history of electronics. Why can’t we learn something from the above philosophers and great inventors for bettering our world and technology? Please share your views on this article in the comment section below.