Hey Bostjan, Thanks for your comment, and this circuit just explains the basic concept behind voltage control tunning through tunnel diode, whereas the voltage divider is formed between R1 and Rw1 and also by varying inductor values we can change the resonant frequency of the Inductor Capacitor LC circuit. This reduces the overall capacitance and the capacitance range by half, but has the advantage of reducing the AC component of voltage across each device and has symmetrical distortion should the AC component possess enough amplitude to bias the varicaps into forward conduction. Some disadvantages are reverse-biased operated so no current flows. King of physics constant pagl 11,570 views It is used in storing the charge. This circuit cannot work in practice. Advantages of varactor diode. This makes a varactor diode ideal for being used in circuits that require voltage-controlled tuning. So, every P-N junction has a depletion region in between, and this depletion region width is dependent upon the voltage. Transistor Configurations | Common Emitter, Base and Collector Circuits. Varactor diodes are also referred to as varicaps or tuning diodes. The Varactor diodes belong to the family of semiconductor devices. A varactor diode is a simple variable capacitor that allows oscillator circuits and other circuits to be easily tuned by applying a voltage. What is Varactor Diode | Construction, Working, Characteristics, And Applications, Download any E-Book for Free from Z-Library, varactor diode advantages and disadvantages, voltage controlling tuning circuit using Varactor diode, BARITT Diode? Given fig: below shows the curve between reverse bias voltage VR across varactor diode and total junction capacitance CT. Indicate which of the following diodes will produce the highest pulsed power output: a. Varactor. the voltage required to set the varactor diode capacitance. The diode whose internal capacitance varies with the variation of reverse voltage such type of diode is known as the varactor diode. It is one type of twisted pair cable. Working, Construction Applications (2019). So, this region, where it is depleted of carriers, is called the depletion region. A hexagonal cell  method is on... Zigbee network technology is a wireless protocol used for wireless networking and connectivity. Applications of Varactor Diode: variable diodes are used in a variable resistant tank, which is generally an L-C circuit. Powered by. used to achieve reconfiguration such as PIN diodes, varactor diodes, Micro Electro Mechanical Switches (MEMS) etc. Varactor diodes are mostly used as tuned capacitors and they have significantly replaced mechanically tuned capacitors in various electronic applications. The capacitor C1 is used to prevent the reverse bias for the varactor diode, also avoids the diode getting short circuited through the inductor. varactor diode has Low Noise. But rectification is not all that a diode can do. The varactor diode can be tuned by applying tuning voltage or bias through an isolating series resistor R1. Instead of the 0.6 to 0.7 volts seen with a silicon junction diode, a Schottky diode may turn on with as little as 0.2 or 0.3 volts. When this happens, the region at the junction becomes free of carriers. It generates very less noise as compared to others P-N junction diodes. Given Fig: below shows the use of varactor diode in a tuned circuit. Varactor diode 1. c. Schottky barrier. Thus RW and R1 form a voltage divider which is used to measure the amount of reverse bias voltage across the varactor diode D1 and therefore its capacitance. Thus, the power loss due to noise is low in varactor diodes. A varactor is always operated in reverse bias and it produces capacitance effect, this is because its anode and cathode terminals act as the plate of the capacitor and the free space between them acts as a. It has small size and portable you can use it in circuits easily. Moreover it is used to protect electronic components which are vulnerable to reverse voltages. Here this article gives the advantages and disadvantages of the Zener diode to better understand this topic. This is all about Varactor Diode Working, Construction, and Practical Applications, and if you like our post give a thumbs up and comment below to appreciate the work and stay connected with us. 5.4. Some advantages of varactor diode is function of the voltage that impressed on its terminals. Thus, by decreasing reverse bias will decrease the resonant frequency and vice-versa. So, we can conclude that the depletion layer width is dependent on the applied voltage. Advantages of Varactor Diode. The property of varying capacitance is utilized to achieve a, When a P-N junction is formed, the depletion layer is created in the junction area. It is economical. A Diode is an electronic component that has two terminals and allows current to flow only in one direction. The V-I characteristics of the diode are non-linear and it permits the flow of current in only one direction In forward bias mode, the diode allows the flow of curren… The oscillator can be enabled by tuning the diode D1. the power loss due to noise is low in varactor diodes. Topic: Varactor Diode Name: Abdul Mohiz Roll No: CS-15-41 2. o A varactor is a diode that always works /operates in reverse bias and is doped to maximize the inherent capacitance of depletion region. The resistance RW in the circuit is the resistance of inductor’s winding. First, they have very fast switching times, perhaps orders of magnitude of improvement. When the junction is forward biased, the barrier potential for these carriers decreases; so there is the notable amount of free carriers moving from this (electrons and holes), due to that moment it constitutes a current; hence large current can flow. It … When the junction is reversed biased; the potential barrier is increasing; the reverse bias will help this potential barrier to get increased. Consider the PN junction, The P-type is consisting of free carriers which are called holes, and N-type is consisting of free carriers which are called electrons. Because they have a tendency to merge with each other; the hole has a tendency to merge with the electron and vanish. Advantages of Varactor Diode The following are the advantages of the varactor diode. It is reliable you can use it to vary capacitance. Low Noise: It generates less noise as compared to the other P-N junction diode. o The P and N region are conductive and acts as the capacitor plates. 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