State the applications of zener diode

What Is a Zener Diode? A Zener diode is a special type of rectifying diode that can handle breakdown due to reverse breakdown voltage without failing completely. Here we will discuss the concept of using diodes to regulate voltage drop and how the Zener diode operates in reverse-bias mode to regulate voltage in a circuit. How Diodes Regulate Voltage Drop If we connect a The current through a forward-biased PN junction is proportional to e raised to the power of the forward voltage drop. Because this is an exponential function, current rises quite rapidly for modest increases in voltage drop. Another way of considering this is to say that voltage dropped across a forward-biased diode changes little for large variations in diode current. In the circuit shown in figure (a) below, diode current is limited by the voltage of the power supply, the series resistor, and the diode’s voltage drop, which as we know doesn’t vary much from 0.7 volts. Forward biased Si reference: (a) single diode, 0.7V, (b) 10-diodes in series 7.0V. If the power supply voltage were to be increased, the resistor’s voltage drop would increase almost the same amount, and the diode’s voltage would drop just a little. Conversely, a decrease in power supply voltage would result in an almost equal decrease in resistor voltage drop, with just a little decrease in diode voltage drop. In a word, we could summarize this behavior by saying that the diode is regulating the voltage drop at approximately 0.7 volts. The...

Click to view the Simulator >> Aim To construct a zener diode voltage regulator and measure its line and load regulation. Apparatus Zener diode, resistor, variable DC power supply, milliammeter, voltmeter, Rheostat and wire. Theory The Zener diode is like a general-purpose signal diode. When biased in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents. Avalanche Breakdown: There is a limit for the reverse voltage. Reverse voltage can increase until the diode breakdown voltage reaches. This point is called Avalanche Breakdown region. At this stage maximum current will flow through the zener diode. This breakdown point is referred as “Zener voltage”. Fig 1: Zener diode The Zener Diode is used in its "reverse bias". From the I-V Characteristics curve we can study that the zener diode has a region in its reverse bias characteristics of almost a constant negative voltage regardless of the value of the current flowing through the diode and remains nearly constant even with large changes in current as long as the zener diodes current remains between the breakdown current I Z(min) and the maximum current rating I Z(max). This ability to control itself can be used to great effect to regulate or stabilise a voltage source against supply or load variations. The fact that the voltage across the diode in the breakdown region is almost constant turns out to be an importa...

They are heavily doped than normal p-n junction diodes, thereby forming a very thin depletion region. This makes them capable of reverse breakdown at relatively low voltages (Typically less than 4V). Also, after reverse breakdown, the voltage across them stays fairly constant. This makes it suitable for use as voltage regulators. Image source: During the reverse bias it conducts only a small leakage current. If the voltage in reverse mode increases to specified breakdown voltage (Vz) then, the flow of current from diode begins. A series resistor indicates that the current reaches the maximum first and after that it gets stabilized and then, for the wide range of applied voltage, it remains constant. Symbol of Zener Diode The picture shows the standard symbol of Zener diodes with the anode and cathode marked on respective sides. In an actual device, the cathode is indicated with a thick line. -iz indicate the reverse current flow after Zener breakdown. V-I Characteristics of Zener Diode When the anode is connected with the positive terminal of the supply it is considered to be in forward bias and when the anode is connected to the negative terminal of the supply reverse biased mode. V-I characteristics of a Zener diode. Forward Characteristics of Zener Diodes When forwards biased it works similar to the p-n junction diode. It has a bias voltage between 0.3V0.7V. It has the forward bias characteristics which are represented in the first quatrain of the V-I characteristics. R...

Rectification The rectification can also be classified into Half Wave Rectification When only one half of the AC cycle i.e. positive half cycle or negative half cycle is rectified or converted into DC, the rectification is called half-wave rectification. Such rectifiers only use one diode and have very low efficiency and Full Wave Rectification When the full-wave both positive and negative half cycles of the alternating current is converted into DC is called full-wave rectification. Such rectifiers use 4 diodes having maximum efficiency and power ratings. It is also known as full bridge rectifier. In simple words, rectification is one of the finest applications of diodes. Related Articles: • • Difference Between Diode and SCR (Thyristor) Switching A diode is basically a Such a switching property of the diode is used in logic gates. Although diodes are not used in the modern logic circuits due its low switching speed and losses but one can easily make the Clipper Clipper is a circuit mainly consisting of diodes. It is used for shaping an AC signal or waveform. It is used for clipping or cutting a portion from either positive or negative or both halves of the waveform above or below a threshold level. It changes the shape of the signal. The peak to peak value of the output waveform changes however, there is no DC offset. Clamper A clamper is a circuit that adds in a positive or negative DC shift to the Voltage Multiplier A voltage multiplier as its name suggests multiplies t...

Zener diodes are a type of diode that can be used in a variety of different ways. They are designed to allow current to flow in one direction only, and they are used to regulate voltage. Zener diodes have a wide range of applications, and they can be found in a variety of different devices and electrical circuits. In this article, we will take a closer look at what zener diodes are and how they are used. We will also explore some of the most common applications for these devices. Let’s start by taking a look at what a zener diode actually is. What Is A Zener Diode? A zener diode is a type of semiconductor device that is used to regulate voltage. It is made by reversing the p-n junction of a conventional diode. When biased in the reverse direction, it breaks down at a specific voltage known as the zener voltage. This breakdown voltage can be controlled by doping the p-n junction with impurities. Zener diodes are a specific type of Zener diodes can operate under a range of varying voltages. This is one of their key benefits as they still can maintain a consistent voltage drop across the diode even when the input voltage range varies. The level of current that flows through a zener diode does not affect the voltage level. Even with a varying level of current, the level of voltage will stay stable and nearly the same. When a zener diode is operating in the forward bias it operates like a standard diode. When they are used in reverse bias the diode will typically have a small l...

Advantages of Zener Diodes for Circuit Functionality Posted September 17, 2020 A zener diode is a type of rectifying semiconductor diode that is used to regulate voltage in a circuit, working in a reverse-bias mode to avoid failure. Semiconductor diodes allow a current to flow in only one direction, but zener diodes allow the current to also flow in the opposite direction when exposed to enough voltage. Below, Solid State Inc. reviews the applications, operations and advantages of zener diodes. What is the Difference Between a Diode and a Zener Diode? As noted, a diode is a semiconductor that conducts in a single direction only, whereas a zener diode conducts in both forward and reverse biased directions. If a normal diode operated in reverse, it would be destroyed, though no damage occurs with a zener diode. Instead, zener diodes take full advantage of the amount of reverse voltage applied. Zener Diode: Basic Operations and Applications Zener diodes operate the same as a PN junction diode when in the forward-bias direction, but it’s typically used for the reverse mode in its applications. That said, zener diodes also regulate voltage one way (regular) or both ways (bidirectional). It has a wide variety of voltages and, as reverse voltage increases to its breakdown voltage, a current will start to flow through the diode. Because the voltage remains fairly constant across a wide range of power supplies, these are used for voltage regulation, surge suppressors, clipper circu...

Introduction Diodes generally are known as a device that allows the flow of current in one direction (forward biased) and offers resistance to the flow of current when used in reverse bias. Zener Diode (Named after the American scientist C. Zener who first explained its operational principles) on the other hand, not only allow the flow of current when used in forward bias, but they also allow the flow of current when used in the reversed bias so far the applied voltage is above the breakdown voltage known as the Zener Breakdown Voltage. Or in other words Breakdown voltage is the voltage, on which Zener Diode starts conducting in reverse direction. Operational Principle of Zener Diode: In normal As the reverse voltage applied to the Zener diode increases towards the specified Breakdown Voltage (Vz), a current starts flowing through the diode and this current is known as the Zener Current and this process is known as Avalanche Breakdown. The current increases to a maximum and get stabilized. This current remains constant over the wider range of applied voltage and allows the Zener diode to withstand with higher voltage without getting damaged. This current is determined by the series resistor. Consider the Images below of a normal diode in action. To show the operations of the zener diode, consider the two experiments (A and B) below. In Experiment A, a 12V zener diode is connected in reversed biased as shown in the image and it can be seen that the zener diode blocked the v...

Uses Of Diode We are aware of diodes as the device with two active electrodes and two terminals allowing current to pass through it only in one direction. One of the core uses of diodes is blocking current flow in one direction and allowing the current to flow in another direction. Following is the table of links for other related concepts of diode:: How do diodes work? Before knowing the uses of diodes, we should know that an ideal diode is enclosed in a plastic or glass case to mark the cathode side of it. There are two ways a diode functions, either it is a forward-biased or it is reverse-biased. FORWARD-BIASED REVERSE-BIASED Current flows from anode to cathode. Current flows from cathode to anode Let us consider a P-N junction type diode; If the diode is in forward bias, the P-type region is connected with the positive terminal of the voltage source and N-type to the negative terminal. Electrons will get attracted to this terminal and will form a covalent bond with the P-type material. So, without any hindrance, the When the diode is in reversed bias, the P-type region is connected to the negative terminal and the N-type region is connected to the positive terminal of the source. Because the positive terminal is connected to N-type, the free electrons are attracted towards that region due to the presence of positive terminal. Applications and Uses of diodes There are various types of diodes and these diodes are used in numerous ways. • The most basic function would be ...