Lecture series on electronics for analog signal processing i by prof. The pn junction diode is the typical diode that has been used in the previous circuits. A pn junction diode is formed by placing a pdoped semiconductor next to an ndoped semiconductor. Lecture 5lecture 5 pn junction diodes quantitative. Chitralekha mahanta, department of electronics and communication engineering,iit guwahati. Wei es154 lecture 8 5 characteristics of junction diodes given a semiconductor pn junction we get a diode with the following characteristics. Biased pn junction diodes forward biased and reverse biased pn diodes depletion capacitance of pn junction diodes minority and majority carrier distributions in a biased pn junction diodes carrier transport and current flow in biased pn.
Are used to allow current to flow in one direction while blocking current flow in the opposite direction. Proone is a product from that helps in the preparation of technical competitive exams such as gate, ies, drdo, barc, jto, etc. They are also called pn diodes in analogy with vacuum diodes. Nptel provides elearning through online web and video courses various streams. Lecture 15 the pn junction diode i iv characteristics november. The pn junction has been the most common rectifier used in the electronics industry. Gilbert ece 340 lecture 27 102912 zener breakdown last time we talked about zener breakdown the zener effect is the breakdown mechanism if the reverse bias required to force breakdown occurs at low voltages. Radhakrishna rao, department of electrical engineering,iit madras. Morris 2 majority carrier diffusion barrier lowered balanced by diffusion reduced diffusion increased minority carrier drift drift enhanced.
Nptel analog electronics free video lectures, courses, tutorials, classes, clips electronics lectures from mit, stanford electronics video classes from iit delhi, mumbai, kharagpur. A pn junction with open terminals excluding minority carriers f. Lecture 5lecture 5 pn junction diodes quantitative analysis math, math and more math georgia tech ece 4833 dr. Pn junction diodes video lecture, online training material. Najmabadi, ece65, winter 2012 high concentration of h on the p side holes diffuse towards the junction high concentration of e on the n side electrons diffuse towards the junction n side is positively charged because it has lost electrons. A pn junction diode is formed when a ptype semiconductor is fused to an ntype semiconductor creating a potential barrier voltage across the diode junction the effect described in the previous tutorial is achieved without any external voltage being applied to the actual pn junction resulting in the junction being in a state of equilibrium. Lecture 7 large and small signal modelling of pn junction diodes in this lecture you will learn. Turn on voltage based on the builtin potential of the pn junction reverse bias breakdown voltage due to avalanche breakdown on the order of several volts. They are referred to as photoelectrons and photoholes the applied voltage separates the photocarriers attracting electrons toward. Contains a ptype and an ntype region in a closed boundary.
Our pn junction behaves kind of like an ideal diode. Develop an understanding of the pn junction diode and its behavior. A k schematic symbol for a pn junction diode p n representative structure for a pn junction diode. Introduction to semiconductors, how pn junction is formed.
Bold indicates devices covered in depth in ece 3040. Depletion layer capacitance equal amount of charge on each side, opposite charge propagation of depletion region caused by the doping differentiation gives the. Contd notes and anderson2 sections part 2 preface and sections 5. Smith department of eecs university of california, berkeley eecs 105 spring 2004, lecture 19 prof. Such junctions show a pronounced rectifying behavior. A pn junction is the metallurgical boundary between the n and pregions of a semiconductor crystal. Lecture 15 the pn junction diode i mit opencourseware. Diodes what are diodes pn junction forward bias reverse bias zener diodes.
Radhakrishna rao, department of electrical engineering,iit. Parasuraman,department of metallurgy and material science,iit madras. Lecture 6 biased pn junction diodes and current flow. Review, pn junctions, fermi levels, forward bias prof j. Poissons equation, work function, ms energy band diagrams lecture 9. Iv characteristics, practical ohmic contacts, smallsignal capacitance pn junction diodes lecture 10. A pn junction diode in thermal equilibrium you have already seen a pn junction diode in thermal equilibrium. Pn junction diode lecture 2 outline about pn diode pn junction formation pn junction realization barrier height thermal equilibrium equilibrium depletion approximation abrupt junction pn junction bias. At the instant of the pn junction formation, the free electrons near the junction in the n region begin to diffuse across the junction into the p region where they combine with holes near the junction. Diodes in the first lecture, we discussed linear circuit components resistors, capacitors, and inductors.
Consider the heavily doped pn junction shown to the left and then apply a reverse bias to the junction. Lecture 1 introduction to semiconductor devices reading doolittle. Electronic materials, devices, and fabrication by prof s. Module 1 lecture 2 pn junction diodes lecture series on basic electronics by dr. Premature breakdown mitigation requires edge engineering.
But not exactly even if the external voltage or bias. Circuit models of pn junction diodes small signal modeling of nonlinear circuit elements small signal models of pn junction diodes junction resistance and capacitances ece 315 spring 2006 farhan rana cornell university. Which are the best nptel lectures regarding electronic devices and. Nptel video lectures, iit video lectures online, nptel youtube lectures, free video lectures, nptel online. Video created by georgia institute of technology for the course introduction to electronics. Also, it explains the phenomenon of shockleyqueisser limit. Photodetectors pn junction can detect light when reverse biased ptype ntype when the light illuminates the pn junction, the photons energy releases free electrons and holes. Lecture 16 the pn junction diode ii mit opencourseware. Video lesson pn junction diodes video lecture, online training material, list videos, quiz, materials, useful links, documents and discussions for pn junction diodes video lecture, online training material. The pn junction is a versatile element, which can be used as a.
Smith abrupt junction, full depletion model for the abrupt junction, full depletion model of the pn diode, we can find the potential as a function of position by integrating over the charge. Octavian florescu 2 the pn junction diode schematic diagram. The pn junction diode the negative terminal of the biasvoltage source pushes the conductionband electrons in the n region toward the pn junction, while the positive terminal pushes the holes in the p region toward the pn junction when it overcomes the barrier potential v b, the external voltage source provides the n region electrons with enough energy to penetrate the. Part 5 large signal complete model and small signal limited use models of a diode reading. Iit bombay, for topics like led,laser,photodiode etc. Lecture 6 biased pn junction diodes and current flow in this lecture you will learn. Lecture 2 diode lecture series on electronics for analog signal processing i by prof. Schottky diodes, tunneling diodes, pnjunctions are the most common. Pn junctions consist of two semiconductor regions of opposite type.
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