The increase in resistance of the pn junction results in the junction behaving as an insulator. The other differences between the pnjunction and zener diode are shown in the comparison. A semiconductor diode is prepared by joining p and n sections of a semi conducting material like germanium or silicon. The vi characteristics of pn junction diode in forwarding bias are nonlinear, that is, not a straight line. 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. To verify the vi characteristics of pn junction diode and zener diode. In this experiment, we try to observe the relation between the voltage and corressponding current generated. Pn junction is also a fundamental building block of many other semiconductor electronic devices such as transistors, solar cells, light emitting diodes, and integrated circuits. Working of pn junction diode with biasing, characteristics.
If we join a piece of p type material to a pieceof n type material such that the crystalstructure remains continuous at the boundary, a. Iv characteristics uthe barrier increase reduces the majority carrier diffusion to a negligible level uthe pside electrons and nside holes can wander into the depletion region and be swept to the other side a reverse inap ureverse bias situation aan increase of the potential hill ubeing associated with. Thus the vi characteristics of pn junction diode is verified. It is seen that the forward current rises exponentially with the applied forward voltage. We can then fill in the junction region of the band diagram as.
Pn junction diode characteristics electronic circuits and. Apr 05, 2019 working of pn junction diode if an external potential is applied to the terminals of pn junction, it will alter the potential between the p and nregions. The circuit connection for determining the vi characteristics of a pn junction is shown in the figure below. Simulation using multisim of pn junction diode characteristics.
To study and verify the functionality of pn junction diode as series and shunt clippers. There are two operating regions and three possible biasing conditions for the standard junction diode and these are. A key difference is that a pn diode contains two depletion regions of opposite type. Experiment 1 vi characteristics of diode1vi characteristics of diode aim. Determine exponential diode model parameters is and n from voltage and current data. In this lab you will measure the iv characteristics of the rectifier and zener diodes, in. This phenomenon creates a depletion layer do check out diode application in clamper circuit in this practical we will learn to obtain and draw the graph of vi characteristic of a pn junction. Jan 21, 2019 voltampere vi characteristics of a pn junction or semiconductor diode is the curve between voltage across the junction and the current through the circuit.
The diode has two terminals called a cathode and an anode. Understanding the operation of biased pn junction rectifier diodes. Semiconductor, silicon, pn junction, forward bias, reverse bias, diode. The circuit connection for determining the v i characteristics of a pn junction is shown in the figure below. Vi characteristics of pn junction diode topics covered. Diode iv characteristics contents that should be delivered for every report. The credit of discovery of the pn junction goes to american physicist russel ohi of bell laboratories.
Semiconductor physics semiconductors and diodessemiconductors. The graph shows the reverse vi characteristics of the given pn junction diode. Draw the vi characteristics of pn junction diode and explain the operation of diodes as with other semiconductor devices is often described by a special graph called a characteristic curve. Pn junction diode applications pn diode applications. Experiment 16 the pn junction introduction in this experiment on the physics of the pn junction, a determination is made of both the universal constant ek i. Zener effect dominates at reverse voltages less than 5 volt whereas avalanche effect dominates above 5 v. This nonlinear characteristic illustrates that during the operation of the n junction, the resistance is not constant. Measure and plot the v i terminal characteristics of pn junction diodes. A perfect diode is a device that only allows current to flow through it in one direction, i. An ammeter is connected in series and voltmeter in parallel, while the supply is controlled through a variable resistor.
To obtain vi characteristics of pn junction diode electronics practical when p and n semiconductors are joined to make the pn junction semiconductor diode, the electrons near the pn junction jump from n to p and holes near the junction jump from p to n. Simulator procedure as performed through the online labs select the characteristics of diode from the drop down list. The other differences between the pn junction and zener diode are shown in the comparison chart. Experimental methods py2108 2 1 learning objectives the objectives of this practical section are to 1.
The pn junction is the fundamental building block of the electronic age. Practical report on diode characteristics pdf scoop. Pn junction diode in the reversebiased configuration is sensitive to light from a range between 400nm to nm, which includes visible light. Pn junction diode and characteristics of pn junction diode. A pn junction diode is a twoterminal electronics element, which can be classified as either. In forward bias condition, current is constant until certain voltage is reached. The v i characteristics or voltagecurrent characteristics of the pn junction diode is shown in the below figure. However, at ordinary room temperature, a potential difference of about 0. The diode is a device formed from a junction of ntype and ptype semiconductor material. Usually, voltage is taken along xaxis and current along yaxis. To study and draw the characteristics of half wave and full wave rectifiers. May 20, 2016 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.
Pn junction diode vi characteristics using multisim youtube. A practical circuit arrangement for a pn junction diode is as shown in the following figure. It means that a zener diode can be used as an alternate current path. This causes electrons from nregion to get attracted to positive terminal of the battery and holes by the negative terminal. The vi characteristics of junction diode in forward and reverse bias condition has been be plotted on the graph. It is also required to obtain the capacitancevoltage characteristics of the diode. Vi characteristics of pn junction diode electronics post. The current through an ideal pn junction is given by the diode equation. The reverse breakdown of a pn junction may occur either due to zener effect or avalanche effect. Normally the voltage is taken along the xaxis and current along yaxis. Zener diode is a reversebiased heavilydoped pn junction diode which operates in the breakdown region.
To study the forward and reverse bias characteristics of diode and zener diode. Jan, 2015 pn junction diode characteristics lab expriment 1. 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 and therefore we can not described its operation by simply using an equation such as ohms law. What is the effect of temperature in the diode reverse characteristics. As shown in the figure, pn junction diode is a 2 terminal polarity sensitive device.
To study the vi characteristics of a semiconductor diode. Pdf v i characteristics of diode through computer researchgate. Basic electronics notes on vi characteristics of zener diode. Plot a graph with reverse voltage along x axis and reverse current along y axis. In this article, we will focus on the iv characteristics of the junction diode, specifically the pn junction.
There is also a difference in the reverse bias region due to both material characteristics and fabrication of the diode junction. The vi characteristics or voltagecurrent characteristics of the pn junction diode is shown in the below figure. A typical vi characteristic for a forward biased pn junction is shown in the figure below. The semiideal diode had a leakage current across the junction the reverse saturation current, shown by i. While doing the experiment do not exceed the ratings of the diode. The vi characteristics of a zener diode can be divided into two parts i forward characteristics. Other semiconductor components are made from more complicated arrangements. Pn junction diode junction diode symbol and static iv characteristics. The pn junction biasing the pn junction the diode trouble shooting. A light emitting diode led is essentially a pn junction diode.
The constant vz developed across the diode can then be applied to a load. When p and n semiconductors are joined to make the pn junction semiconductor diode, the electrons near the pn junction jump from n to p and holes near the junction jump from p to n. 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. Pn junction diode baising and its vi characteristics. To study and verify the functionality of a pn junction diode in forward bias b pointcontact diode in reverse lab report 1. This paper shows the vi characteristics of diode through pc that records the. Silicon a single silicon atom consists of fourteen negatively. 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. Thus the load voltage remains at constant by altering the current flow through the zener diode. Pn junction diode is one of the fundamental elements in electronics. Iv characteristics pn junction diode reverse biasing a pn junction when the polarity of the battery is reversed, the cathode is connected to positive end of the battery and anode to negative.
This time consists of a transient and an interval of time before the diode attains a steady state. Voltampere v i characteristics of a pn junction or semiconductor diode is the curve between voltage across the junction and the current through the circuit. If we join a piece of p type material to a pieceof n type material such that the crystalstructure remains continuous at the boundary, a pn junction is formed 2. This pn diode applications are very useful for beginners. Basic electronics notes on vi characteristics of zener. Characteristics of junction diodes technical articles. Configure an oscilloscope in xy mode to display the v i characteristics of a diode curve tracer. Forward bias current flows reverse bias no current flow. The ratings of a diode as stated earlier are the limiting values of operating conditions, which if exceeded could cause damage to a diode by either voltage breakdown or overheating. Figure below shows that the circuit diagram to determine the vi characteristic of a pn junction. Electrostatic analysis of a pn diode pn juntion diode.
Conduct the experiment for obtaining the forward bias vi characteristics of the given diode. A pnjunction 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. The diode conducts when forward bias is applied and it will introduce zero resistance in the circuit. 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. A very small current will made at the junction due to the movement of minority charge carriers across the junction. Working of pn junction diode if an external potential is applied to the terminals of pn junction, it will alter the potential between the p and nregions. A pn junction diode is a twoterminal electronics element, which can be classified as either step graded or linear graded. By exploring the electrical properties of silicon, it is possible to acquire an understanding of the inner workings of the pn junction. In this type of diode, we dope one side of a semiconductor piece with an acceptor impurity and another side with a donor impurity. Connecting a pn junction to an external voltage source is.
Understand the behaviour of a diode under forward and reverse bias and be able to plot the iv characteristic of an ideal diode 3. Vi characteristics of pn junction diode in 3biasing modes. 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. Jul 27, 2018 1 compare the the purpose of this lab is to study the characteristics of the diode. Zero bias no external voltage potential is applied to the pn junction diode. But simulation doesnt necessarily give the true effect of any experiment as the. Voltampere characteristics of diode in forward bias condition. Voltampere vi characteristics of a pn junction or semiconductor diode is the curve between voltage across the junction and the current through the circuit. Definition ptype semiconductor is suitably joined to ntype semiconductor,to conduct surface is called pn junction. In general, the cathode of a diode is marked by a solid line on the diode. The slope of the pn junction diode in forwarding bias shows the resistance is very low. This potential difference can alter the flow of majority carriers, so that the pn junction can be used as an opportunity for the diffusion of electrons and holes.
The lead connected to the ptype material is called the anode and the lead connected to the ntype material is the cathode. The horizontal line in the below figure represents the amount of voltage applied across the pn junction diode whereas the vertical line represents the amount of current flows in the pn junction diode. The analysis is very similar to that of a metalsemiconductor junction. Jan 29, 2019 pn junction diode is one of the fundamental elements in electronics. Mar 23, 2018 simulation using multisim of pn junction diode characteristics. 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. P type and n type semiconductors, takenseparately are of very limited use. It generally shows the relation between bias voltage and current of a diode. Some of the voltage and current division lab report. This page of application notes section covers pn junction diode applications. Understand the physics of a pnjunction and how a junction diode is created 2.
An isolated pn junction makes a semiconductor diode. Most of the commercial leds are realized using a highly doped n and a p junction. The prelab and postlab report format is as follows. When carriers are injected across a forwardbiased junction, it emits incoherent light. Experimently find out whether the given diode is made of germanium or silicon. The major difference between pn junction and the zener diode is that the pn junction diode allows current to pass only in the forward direction, whereas the zener diode allows the current to flow both in the forward and the reversed direction. Voltage ampere or vi characteristics of a pn junction are the curve between voltage across the junction and the circuit current. Pn junction diode characteristics explained in detail.
A pn junction with open terminals excluding minority carriers f. To study and draw the characteristics of rectifier filter circuit. Image source forward biasing a pn junction diode is very simple. Note to those familiar with a diode turn on voltage.