Types of varactor diodes abrupt and hyper abrupt type. Presented here is a lowpower fm transmitter with varactor diode tuning using surfacemount devices smd that will be received with a standard fm radio. Recipe for solving diode circuits state of diode is unknown before solving the circuit 1. Varactor diode or varicap diode working and applications a varactor diode is a pn junction diode that changes its. Varactor diode nyamador enock seth university of mines and technology umat, tarkwa computer science and engineering 14 twitter.
These powerpoint shapes are shown in white, against a blue background. Write down all circuit equations and simplify as much as possible 2. Jul 31, 2018 varactor diode is a reverse biased pn junction diode, whose capacitance can be varied electrically. The form of junction in the diodes has a major impact on the properties and performance. Ppt specialpurpose diodes powerpoint presentation, free. Find powerpoint presentations and slides using the power of, find free presentations research about diode rectifiers ppt. Describe the varactor diode and its variable capacitance characteristics. One of the most major applications for varactors are in tuning circuits, where they function to modulate or in simple terms, vary fm waves so that we get our different fm channels, so that you can change to different stations.
Varactor diode notes edurev notes for is made by best teachers who have written some of the best books of. In view of the fact that the varactor diode is a semiconductor diode, many parameters are the same as those of other diodes. Workable on 230 volts, ac fitted with zener diode 8. An additional electrons from the n region are repelled by the net negative charge of the p region. Because the phase of the carrier is shifted, the resulting signal has a frequency which is. Chapter 3 specialpurpose diodes powerpoint ppt presentation. Varactor diode working, characteristics and its applications. A diode is also a tool that exclusively permits unidirectional flow of current if the diode is operated at a particular voltage level. Varactor tuning circuit explained learning about electronics. Varactor diode definition, symbol, construction and.
Varactor diode a microwave solidstate devices also called a parametric diode, tuning diodes or varicap diodes a nonlinear device provides a voltagedependent variable capacitance 3. Diode, semiconductor material, such as silicon, in which half is doped as pregion and half is doped as nregion with a pnjunction in between. 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 voltagedependent capacitance of a reversebiased pn junction. Mouser is an authorized distributor for many varactor diode manufacturers including diodes inc. And were looking, now, at a device called a varactor diode. Introduction varactor diode is a special type of pn junction diode, in which pn junction capacitance is controlled using reverse bias voltage.
Great powerpoint template for presentations on electronics, semiconductor materials, radio demodulation, overvoltage protection, etc. Explain how a zener is used in voltage regulation and limiting. May 12, 2014 varactor diode a microwave solidstate devices also called a parametric diode, tuning diodes or varicap diodes a nonlinear device provides a voltagedependent variable capacitance 3. Varactor diode definition, symbol, construction and working. Diodes exclusively block current in the reverse direction whereas the reverse voltage is within a restricted vary and if not reverse barrier breaks and conjointly the. Required optical density for the laser protective eyewear. Power supply, output and meters connections are brought out on the panel. Voltage control oscillators are used extensively in transmission and receiving circuits in communication. It always works in reverse bias condition and is a voltagedependent semiconductor device.
A varactor diode circuit for indirect fm is shown in figure 3. The modulating signal varies the capacitance of the diode, which then changes the phase shift incurred by the carrier input and thus changes the phase of the output signal. Varactor diodes are available at mouser electronics from industry leading manufacturers. Ppt varactor diode powerpoint presentation free to view. Dec 11, 2017 diode seminar ppt and pdf report download. Soldering surface mounted devices is not so hard and actually is quite easy. Varactor diodes are specially designed to take advantage of this characteristic and are used as voltage controlled capacitors rather than traditional diodes. And varactor diode plays a significant role in construction of voltage controlled. The varactor diode is a pn junction diode whose capacitance is varied by varying the voltage. And at one end this diode is inbuilt with two lines that specify the capacitor symbol. It is a pn junction with a special impurity profile, and its capacitance variation is very sensitive to reversebiased voltage. Use the diode equation for that state to solve the circuit equations and find i d and v d 3.
Ppt zener diode applications powerpoint presentation free. Varactor diode is also sometimes referred to as varicap diode, tuning diode, variable reactance diode, or variable capacitance diode. It is well known that the operation of the pn junction depends. Macoms gaas and silicon varactor tuning diodes provide broadband performance ranging from 10 mhz to 70 ghz. This video describes in detail, what is a varactor diode, structure of varactor diode and. Lets look into the construction, working of diode, characteristics and applications of varactor. Lets look into the construction, working of diode, characteristics and applications of varactor diode authorstream presentation. Find powerpoint presentations and slides using the power of, find free. Varactor diodes help in achieving frequency modulation. Zener diode applications chapter 3 overview zener diodes zener characteristics zener diodes diode types rectifier zener lower vz due to more heavily.
Before going to varactor diode, lets first take a look at the capacitor. Radhakrishna rao, department of electrical engineering,iit madras. Zener diode characteristic apparatus electronics equipmentzener diode characteristic apparatus with build in stabilized power supply. Aug 31, 2008 lecture series on electronics for analog signal processing i by prof. Varactor diode is a pn junction diode whose capacitance is varied by varying the reverse voltage. Varactor diode or varicap diode working and applications. There are two types of fm modulators direct and indirect. The point at which the diode changes from no bias condition to forward bias condition happens when the electron and holes are given sufficient energy to cross the pn junction. The forward bias voltage required for a silicon diode v t 0. Even though i put the 1n4001 back in its drawer after i finished testing it last week i was able to retrieve the same diode for retesting.
Please view our large selection of varactor diodes below. A free powerpoint ppt presentation displayed as a flash slide show on id. Some varactor diodes may be categorised as abrupt and hyperabrupt types these terms may sometimes be seen in the varcator data sheets the terms abrupt varactor diode and hyperabrupt varactor diode refer to the properties of the varactor diode junction. View and download powerpoint presentations on diode rectifiers ppt. To know the varactor diode working principle, we must know the function of capacitor and. As a result these diodes are also referred to as varicaps, tuning diodes, voltage variable capacitor diodes, parametric diodes and variable capacitor diodes. They are most often used in devices that require electronic tuning, such as radios. Varactor diode is the property of its rightful owner. Ppt chapter 3 specialpurpose diodes powerpoint presentation. If so, share your ppt presentation slides online with. Semiconductor devices varactor diode this is a special pn junction diode with an inconsistent concentration of impurities in its pn materials.
Varactor diode definition, symbol, construction and working diode. The different types of varactor diodes are available in the market such as hyper abrupt, abrupt and galliumarsenide varactor diodes. Varactor diode is known by several names as varicap, voltcap, voltage variable capacitance or tunning diode. Varactor diode 1 varactor diode report by john paolo labaro 2 varactor diode also known as varicap diode is a device whose reactance can be varied in a controlled manner with a bias voltage.
And you may recall that when we looked at a diode we have the n. A free powerpoint ppt presentation displayed as a flash slide show on. Due to their remarkable properties, varactor diodes now find extensi,e use everywhere from the audio frequencies to the outer reaches of the extreme microwave frequencies. Varactor diode explained working, specifications and applications of varactor diode duration. When reversebiased, they have a capacitance that varies with an applied voltage. These devices are commonly used in communication systems. Varactor diode in a pn junction a very thin depletion region acts as an insulator of the o rder of 5 x 10 exists on either side of the p and n regions and it separate the p and n regions are acts as conducting plates, as a result this capacitor is formed. Junction capacitance is present in all reverse biased diodes because of the depletion region. Ppt zener diode applications powerpoint presentation. It is composed of a horizontal line attached to a triangle with its tip attached to a vertical line and then another horizontal line.
When choosing a varactor diode from the information on the datasheet, the varactor specifications need to be carefully assessed to see whether its performance meets the needs for the circuit in which it is intended for uses. This design mimics the visual impact of a blueprint. Varactor diode working, structure and applications reverse bias. Jul 09, 2016 the junction capacitance of diodes varies with the amount of reverse bias. Apr 24, 2017 varactor diodes, also called varicaps, are semiconductor devices that behave like variable capacitors. Lecture series on electronics for analog signal processing i by prof. This diode power supply powerpoint template illustrates the symbol for a diode. 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. Powerpoint slide on pn junction diode compiled by paridhi gupta. The varactor diode is manufactured in such as way that it shows better transition capacitance property than the ordinary diodes. A presentation on varactor diode as part of basic electronics course at school. 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. When the changeover pn junction is abrupt then it is called abrupt type. Special diodes varactor diodes diodes and diode circuits.
Find powerpoint presentations and slides using the power of, find free presentations research about varactor diode ppt. Varactor diodes are also referred to as varicaps or tuning diodes. The symbol of the varactor diode looks like a common pn junction diode that includes two terminals namely the cathode and the anode. Ppt varactor diode powerpoint presentation free to. Thus, in communication devices varactor diodes are significant. View and download powerpoint presentations on varactor diode ppt. Discrete semiconductor products diodes variable capacitance varicaps, varactors are in stock at digikey. Semiconductor devices varactor diode tutorialspoint. In a normal pn junction diode, doping impurities are.
925 90 433 1328 763 681 488 1602 659 188 448 205 1536 1379 470 415 552 1282 524 9 306 1399 729 1409 1063 266 900 328 1040 6 1166 1026 526 157