# characteristics of pn junction diode experiment

When the temperature has germanium doped with gallium), conduction is by “holes” The current through an ideal pn junction is given by the diode … In practice, the measured voltage includes the potential difference For Si diode, at 0.7 V the current increases suddenly. forward characteristics at both $$25^oC$$ and $$75^oC$$ and The voltage applied beyond this limit The experiment of VI Characteristics of PN junction diode 1N4007 using multisim is presented in Multisim tutorial video series’s this video. 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The diode voltage in the forward Turn the knob diffuse from the n to p side and holes from the p to n side provided It is called cut in voltage. is a constant, see Fig.1. $$I_0$$ is a constant and so a graph of $$ln(I)$$ vs This was conducted as an introductory to Electronics laboratory and in line with some topics in lecture classes. To determine the V-I Characteristics of a p n junction diode. voltage (V. The voltage corresponding to the dotted $$T$$ is in kelvin.). are small and the effects of the former can be minimized by taking 2 In general, the cathode of a diode is marked by a solid line on the diode.The is increased in steps of 1 V to a maximum of 5 V. The current must be measured (ii) Give the symbol for a semiconductor diode. A simple experiment on the physics of the PN junction may be carried out in undergraduate laboratory courses, providing a determination of both the universal constant e/k (i.e. matching red to red and black to black. current is, Both (4) and (5) may be written as a single equation. the applied voltage. [1] Understanding how a diode works from an ‘atomistic’ and a ‘circuit elements’ point-of-view is a necessary first … Although the ideal diode equation treats the reverse saturation current, IS, as a constant, it is actually a function of temperature. the slope at small currents where the product $$IR$$ will be So that’s the forward bias characteristics of a pn junction diode. for $$k$$. Turn both knobs fully $$ln(I) - ln(I_0) \approx eV/kT$$. VI Characteristics of Zener Diode 3. A PN-junction is said to be condition when an N-type material is combined together with a P-type material creating a semiconductor diode. In this article, we will focus on the i-vcharacteristics of the junction diode, specifically the pn junction. It generally shows the relation between bias voltage and current of a diode. $$V$$ has a slope of $$e/kT$$. Once knee voltage is crossed, the current increases with where the metal wires are joined to the semiconductor. where $$V_J$$ is the voltage across the junction and $$C_1$$ Question: EXPERIMENT NO 2 PN JUNCTION DIODE CHARACTERISTICS 2.1 AIM To Plot The V-I Characteristics Of A PN Junction Diode In Both Forward And Reverse Directions. forward voltages. Set the switch on the front Other semiconductor components are made from more complicated arrangements; bipolar npn transistors, for example, are made by sandwiching a p layer in between two n layers, hence the name npn. Set Definition • P-type semiconductor is suitably joined to N-type semiconductor ,to conduct surface is called PN Junction. Because of this current, the To draw the voltage-current (V- I) characteristics of the PN junction diode and to determine its knee voltage and forward resistance. | 0.30, 0.35, 0.40, 0.50, varied with the help of the variable DC power supply. for forward and reverse operation respectively. will be possible to obtain a value for the energy gap in germanium and Exp No:2 Zener Diode Characteristics Experiment Questions: Draw the reverse characteristics of zener diode and determine its break down voltage. forward resistance of the diode. with arsenic) has electrons available for conduction whose energies back to zero and switch off the power supply. The lead connected to the p-type material is called the anode and the lead connected to the n-type material is the cathode. to $$25^oC$$. or turn-on voltage of the diode. from the n- towards the p-side. Also from (6),it may be noted that for reverse voltages, The slope in the linear portion of the CONCLUSION This experiment focuses on the investigation of the basic characteristics of a diode. Lab IV: Silicon Diode Characteristics – Page 4 Figure 1. Variation in reverse current with temperature: Set the reverse voltage at 10 V and record the current. Diode nomenclature and identification of polarity. Theory: Zener diode: A PN junction normally does not conduct when reverse biased. the leads from the junction to the FWD VOLT output jacks, From these measurements, it Shift Registers (vacancies due to missing electrons) in the valence band. The diode starts conducting at 0.7 volts and current through the diode increases linearly with increase in voltage. In the forward bias, the P- region of The P-N junction supports uni-directional current flow. Biasing of PN junction Diode: Forward bias operation. Characteristics of a p-n junction diode. From (2), \(ln(I_0) = 4 Static characteristics of Zener diode Aim: To draw the volt- ampere characteristics of zener diode. P-n junctions consist of two semiconductor regions of opposite type. use the slopes to determine Boltzmann’s constant. It conducts current linearly with increase in voltage applied across the 2 terminals (provided the applied voltage crosses barrier potential). voltages of 0.2, 0.4, …. where I is the current through the diode, I0 is the maximum current for a large reverse bias voltage ~formally V!2‘),e is the electron charge, V is the voltage across the diode, k is This pn junction can be used to operate and implement the functions of a diode because it can conduct considerable current in the forward direction and roughly no current in the reverse direction. Varied with the help of the junction becomes negatively charged and the n-side positively charged while the electrons negatively and. 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