Electrical energy conversion by converters, the lost history of the transistor, future electronic power distribution systems, basic strategies in power electronics, power devices, mechanical design and cooling techniques, dcdc converters, linecommutated topologies, voltage source inverters, active compensation. Nptel analog electronics nptel video lectures from iits. Diode working principle and types of diode electrical. Diode is an electronic component that allows the flow of electricity in one direction without resistance or with very little resistance while in the opposite direction has. In ideal conditions, this pn junction behaves as a short circuit when it is forward biased, and as an open circuit when it is in the reverse biased. Develop an understanding of the pn junction diode and its behavior. Pn junction diode with milliammeter in series with the diode. As this is relatively small, the sensitivity is not as great as that for some other forms of photo diode.
Difference between pn junction diode and zener diode. Part 5 large signal complete model and small signal limited use models of a diode reading. In the figure, assume that the forward voltage drops to the pn diode d 1 and schottky diode d 2 are 0. When the diode is in forward conduction, the voltage drop across the diode is.
Pn junction diode is one of the fundamental elements in electronics. Definition, symbol, and types of diodes electrical4u. Oct 07, 2008 lecture series on basic electronics by dr. Theory a semiconductor pn junction diode is a two terminal electronic device that allows current in only one direction. Amitava dasgupta, department of electrical engineering,iit madras. Doping with acceptor creates p type semiconductor while doping with donors produces n type. Pn junction tutorial introduction to pn junction diodes. The behaviour of the pn junction with regards to the potential barriers width produces an asymmetrical conducting two terminal device, better known as the pn junction diode.
A pn junction diode is twoterminal or twoelectrode semiconductor device, which allows the electric current in only one direction while blocks the electric current in opposite or reverse direction. A diode is a simple electrical device that allows the flow of current only in one direction. This pn diode applications are very useful for beginners. This presentation is a very informative piece on pn junction diode an important part of electronics education. Ee105 fall 2014 microelectronic devices and circuits. Iv characteristics pn junction diode theory a semiconductor pn junction diode is a two terminal electronic device that allows current in only one direction. Pn junction diode in the reversebiased configuration is sensitive to light from a range between 400nm to nm, which includes visible light. For an unbiased pn junction diode at thermal equilibrium, which of the.
The boltzmann approximation is to say that the resulting current being small compared with the components of this current, we consider that we are still in quasi equilibrium and therefore that the currents equation is still valid by replacing v bi by v. Write down all circuit equations and simplify as much as possible 2. If on denotes conducting state of the diode and off denotes the non conducting state of. Lecture 4 pn junctions diodes alexandria university. Majority carriers that are injected to the oppposite side of the diode under forward bias become minority carriers and recombine. Basic electronics junction diodes there are many types of diodes depending upon many factors such as the frequency used, their working and construction, their applications etc. The pn junction biasing the pn junction the diode trouble shooting. Recipe for solving diode circuits state of diode is unknown before solving the circuit 1. The rest of the model contains pairs of model parameters and values, separated. The other differences between the pnjunction and zener diode are shown in the comparison chart. From the above, it follows that zero power dissipation occurs in an ideal diode. A k schematic symbol for a pn junction diode p n representative structure for a pn junction diode.
A pn junction diode is one of the simplest semiconductor devices around, and which has the characteristic of passing current in only one direction only. When a free electron meets a free hole it can drop into it. The pn junction diode is the basic semiconductor diode format. Volume ii 2nd edition modular series on solid state dev. Note to those familiar with a diode turn on voltage. Pn junction diode 2 diode introduction a diode is formed by joining an ntype semiconductor with a ptype semiconductor. Winner of the standing ovation award for best powerpoint templates from presentations magazine. Pn junction and diodes ii, diode applications i agenda energy diagrams of the pn junction and depletion region diode operation voltage. Chitralekha mahanta, department of electronics and communication engineering,iit guwahati. A pn junction diode is a two terminal single crystal semiconductor device whose one side is doped with acceptors and other side by donors. Fall 2016, electronic circuits this energy loss results in a voltage drop across the pn junction equal to the barrier potential 0. Module 1 lecture 2 pn junction diodes lecture series on basic electronics by dr.
Free electrons on the nside and free holes on the pside can initially wander across the junction. Basic electronics diodes after having known about various components, let us focus on another important component in the field of electronics, known as a diode. Pn junction diode applications pn diode applications. Pn junction diode, characteristics and applications 2020. Semiconductor, silicon, pn junction, forward bias, reverse bias, diode. To study and verify the functionality of a pn junction diode in forward bias b. Semiconductor pnjunction diodes physically, diodes are formed by the interface between two regions of oppositely doped semiconductor i. Forward bias current flows reverse bias no current flow. A pn junction diode is a twoterminal electronics element, which can be classified as either step graded or linear graded. It is used for many forms of rectification for current levels both large and small, as well as high and low voltage levels, and it finds many uses in all manner of electronic circuits. Unit 6 applications of pn junctions and details of metal. In this tutorial, we will learn about pn junction diodes and in particular the characteristics and working of pn junction diode. Are used to allow current to flow in one direction while blocking current flow in the opposite direction. The junction can be formed by the implantation or diffusion of dopants in an wafer.
Although it is not discussed majorly outside the concept of pn junction diode and sometimes the transistor, a pn junction is an essential topic in semiconductor electronics. Gate questions on pn junction diode 1987 to till date 1987. Find materials for this course in the pages linked along the left. Use the diode equation for that state to solve the circuit equations and find i d and v d 3. Learn about different types of diodes, their working, construction and applications. Semiconductor physics semiconductors and diodessemiconductors. The pn junction has the very useful property that electrons are only able to flow in one direction. A pn junction is the simplest form of the semiconductor diode.
The diode is firmed by doping a semiconductor like silicon or germanium with. Pn junction is a significant building block and it is one among the indispensable structures. Pn junction diode and characteristics of pn junction diode. Jan 04, 2020 a pn junction is the simplest form of the semiconductor diode. Diodes and diode circuits tlt8016 basic analog circuits 20052006 20 3. However, unlike a resistor, a diode does not behave linearly with respect to the applied voltage as the diode has an exponential currentvoltage iv relationship. Pn junction underbiasing 14 boltzmanns approximation. The pin photodiode provides additional sensitivity and performance over that of the basic pn. Jul 31, 2017 in this physics digital electronics video lecture in hindi for class 12 we explained forward and reverse bias in pn junction diode in terms of depletion layer and potential barrier.
This understanding will lay a better foundation for exploring further into different aspects of semiconductor electronics. A germanium diode has a low forward resistance of several hundred v. It is followed by the modelname that will be used by diode components to refer to the model. Pn junctions consist of two semiconductor regions of opposite type. These devices may not be a simple pn type diode, but behave electrically identical to a pn junction diode. Smith department of eecs university of california, berkeley eecs 105 spring 2004, lecture 10 prof.
The conversion of alternating current into direct current is known as rectification. Initially vary regulated power supply rps voltage v s in steps of 0. Lecture series on electronics for analog signal processing i by prof. P type and n type semiconductors, takenseparately are of very limited use. The knee voltage of a pn junction diode is approximately equal to the. Smith announcements zthe thursday lab section will be moved an hour later starting this week, so that the tas can attend lecture in another class zreading. The name diode is derived from diode which means a device that has two electrodes. In this type of diode, we dope one side of a semiconductor piece with an acceptor impurity and another side with a donor impurity. Gate questions on pn junction diode 1987 to till date. Due to this characteristic, the diode finds number of applications as given below. Pn junction diode baising and its vi characteristics. Radhakrishna rao, department of electrical engineering,iit madras. Octavian florescu 2 the pn junction diode schematic diagram ptype ntype id. Lecture pn junction and diodes ii, diode applications i.
Under forward bias, how does current in a schottky diode compared to pn junction diode. Radhakrishna rao, department of electrical engineering,iit madras nptel electronics free video lectures, courses, tutorials, classes, clips electronics lectures from mit, stanford. Assuming we know the diode voltage v d, we can calculate the diode current. The resistance ratio indicates the ability of the diode to pass current in one direction and block current in the other direction. Apr 05, 2019 in this tutorial, we will learn about pn junction diodes and in particular the characteristics and working of pn junction diode. Ee105 fall 2014 microelectronic devices and circuits prof. Pn junction diode technology innovation and incubation. Animation how a p n junction semiconductor works forward. A pn junction diode allows electric current when it is forward biased and blocks electric current when it is reverse biased.
A diode is a tiny electronic component used in almost all the electronic circuits to enable the flow of current in only one direction. Worlds best powerpoint templates crystalgraphics offers more powerpoint templates than anyone else in the world, with over 4 million to choose from. This page of application notes section covers pn junction diode applications. Video created by georgia institute of technology for the course introduction to electronics. Read more pn junction diode and its working principle. Pn junction diode plays a vital role in our electronic fields, because of their unique property current flows in only one direction they are used in many electronic or electrical circuits like rectifiers, switches, clippers, clampers, voltage multipliers in this article, we will learn about what is a pn junction diode and how it works and also effect on pn junction diode with different. Lecture 16 the pn junction diode ii mit opencourseware. This simple animation video clearly explains the topics pn junction semi. You just need to take a battery whose values can be varied from o to v volts, connect its positive terminal to the pside of pn junction diode and then connect the negative terminal of battery to the nside of the pn junction diode. The basic pn photodiode is used in a number of instances. Electrons and the holes breakdown through the pn junction and cross. The diode is firmed by doping a semiconductor like silicon or germanium with trivalent impurity e.
Ppt pn junction diode powerpoint presentation free to. If the diode is forward biased, it allows the electric current flow. This is the voltage required to reach a flat band diagram and sets an upper limit typically an overestimate for the voltage that can be applied to a diode before it burns itself up. As shown in the figure, pn junction diode is a 2 terminal polarity sensitive device. Natarajan, department of physics, iit madras for more courses visit. Current characteristic of a diode forward bias reverse bias v. The ideal diode will have zero resistance when forward biased, however real diodes require that the forward bias exceed a threshold voltage v f before forward conduction begins. The pn junction diode is the typical diode that has been used in the previous circuits. When the diode is forwardbiased, it can be used in led lighting applications. A pn junction is the interface between n and p regions. Pn junction diode consider a p type material and n type material are brought together to form a pn junction diode. Image source forward biasing a pn junction diode is very simple. Semiconductor pn junction diodes physically, diodes are formed by the interface between two regions of oppositely doped semiconductor i.
Due to this property the diode is used as a rectifier in the electronic circuits. A pn junction is the metallurgical boundary between the n and pregions of a semiconductor crystal. The diode is said to be forward biased when the anode is more positive than the cathode. So, in this pn junction tutorial, we will discuss some of the basics of a pn junction, how a pn junction is formed, characteristics of pn junction and many other aspects. Working principle pn junction diode diode is forward biased reverse biased condition types of diode. Lecture series on digital integrated circuits by dr.
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