Diode, an electrical component that allows the flow of current in only one direction. A varactor diode is formed by merging a p-type semiconductor material with the n-type semiconductor material. The anode of the diode varactor consists of p+-type doping (boron) diffused from the top polysilicon contact 151. The figure below shows the symbolic representation of a varactor diode: Its symbol is somewhat similar to an ordinary diode. VARACTOR DIODE . A ceramic layer is used to enclose the whole structure of the diode excluding the anode and cathode terminal. Varactor Diodes are available at Mouser Electronics from industry leading manufacturers. How do they work? US5760661A US08/680,303 US68030396A US5760661A US 5760661 A US5760661 A US 5760661A US 68030396 A US68030396 A US 68030396A US 5760661 A US5760661 A US 5760661A Authority US United States Prior art keywords transmission line varactor diodes bias varactor phase shifter Prior art date 1996-07-11 Legal status (The legal status is an assumption and is not a legal conclusion. The Varactor Diode gets its name from the variable nature of the diode its self. a microwave solid-state devices also called a parametric diode, tuning diodes or varicap diodes a nonlinear device. The SMV1405 –SMV1413 series of bare die, epoxy and hermetic packaged silicon abrupt junction varactor diodes is designed for use in VCOs requiring tight capacitance tolerances. Definition: Varactor Diode is a PN junction diode that is especially operated in reverse biased mode. Please view our large selection of varactor diodes below. The increment or decrement in the region of depletion is proportional to the applied reverse voltage. In the case of low-frequency uses, the basic material used is silicon. See more. The specifications for diodes appear in data sheets and provide a description of the performance of the diode. It has three linear regions of conduction: on, off and reverse breakdown. With IS, determines the DC characteristics of the diode. As these are specially designed diodes thus exhibits the characteristic of transition capacitance far better as compared to normal PN junction diodes. The figure representing the construction of a varactor diode is shown below: As we can see here that, n region is connected with the mesa structure. The Varactor Diode gets its name from the variable nature of the diode its self. The SMV1245-011 is a low capacitance, hyperabrupt varactor diode in an SOD-323 package. The word varicap is derived from the combination of word variable and capacitor. Let us first understand why it is not operated in forward biased condition. When a diode is provided forward potential. Mouser is an authorized distributor for many varactor diode manufacturers including Diodes Inc., Infineon, NXP, ON Semiconductor, Skyworks, Toshiba, & more. Which of these is the best description of a zener diode? Varactor diode is also sometimes referred to as varicap diode, tuning diode, variable reactance diode, or variable capacitance diode. VARACTOR DIODE Nyamador Enock Seth University of Mines and Technology (UMaT), Tarkwa Computer Science and Engineering ‘14 Twitter: @enock4seth 2. from Skyworks Solutions, Inc. They are ideal for high Q filter and VCO electronic tuning circuits and are available in die form, flip chip, plastic and ceramic packaging. These are also known as Varicap diodes. Varactors are operated in a reverse-biased state. SILICON VARACTOR DIODE MVAM108 PACKAGE STYLE DESCRIPTION: The ASI MVAM108 is a Silicon Tuning Varactor Diode. But as the reverse potential is applied the majority carriers of both the p and n regions i.e., holes and electrons start moving away from the junction. The cathode is the n-well 41 , which was initially phosphorous-doped, and later n-doped in a multiple ion implantation step to set the varactor characteristics. From the above equation, it is determined that the area of the capacitor is directly proportional to the value of the capacitance. Description: The SMV2020-079LF is silicon hyperabrupt junction varactor diode.The low capacitance range and High Q of this varactor makes it attractive for high frequency and low phase noise VCOs in wireless systems. As we know Zener diode can operate in both reverse biased and forward biasing condition but the varactor diode always function in reverse biasing condition. It is a device whose capacitance varies with the variation in the applied reverse bias potential. The varactor diode is one type of PN junction diode whose internal capacitance changes with the applied reverse bias voltage. A P-N junction diode which acts as a variable capacitor by changing reverse bias is known as a Varactor Diode.. Word Varactor is given to it due to its property of varying capacitance. The Varactor Diode gets its name from the variable nature of the diode its self. The functionality of this diode is dependent on the voltage. Varactor diode operates only in reverse bias. In electronics, a varicap diode, varactor diode, variable capacitance diode, variable reactance diode or tuning diode is a type of diode designed to exploit the voltage-dependent capacitance of a reverse-biased p–n junction. In this video, what is varactor diode, it's working, the applications and some important specifications are explained. Although the terms varactor diode and varicap diode can be used interchangeably, the more common term these days is the varactor diode. 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