Varactor diode construction, working, characteristics. The varactor diode is manufactured in such as way that it shows better transition capacitance property than the ordinary diodes. For comprehensive details of different types of diodes, visit this page. The diode whose internal capacitance varies with the variation of the reverse voltage such type of diode is known as the varactor diode. If positive potential is applied to the top terminal as shown in fig. The varactor diode was named because of the variable reactor or variable reactance or variable capacitor or variable capacitance property of these diodes. The 11th edition of electronic devices and circuit theory by robert boylestad and louis nashelsky offers students complete, comprehensive coverage of the subject, focusing on all the essentials they will need to succeed on the job. We report the theory and design equations of the suspended graphene varactor, wherein device capacitance is tuned by the voltage controlled deflection of a suspended graphene membrane. Theory of the suspended graphene varactor request pdf.
Pdf parametric amplificationmixing using the varactor diode. Varactor diode is also sometimes referred to as varicap diode, tuning diode, variable reactance diode, or variable capacitance diode. Varactor diode symbol in general, it looks like a normal pn junction diode in which one terminal is termed as the cathode and the other terminal is termed as anode. Pdf tuning circuit based on varactor for tunable filter. Varactor diode is a reverse biased pn junction diode, whose capacitance can be varied electrically. A varactor diode also known with the names varicap diode, varactor diode, tuning diode is a pn junction diode which acts as a variable. Pdf electronic devices and circuit theory by robert. Varactor diode is one kind of semiconductor microwave solidstate device and the applications of this diode mainly involve in where variable capacitance is preferred which can be accomplished by controlling voltage.
A varactor diode is considered as a special type of diode that is widely used in the electronics industry and is used in various electronics applications. The varactor diode symbol consists of the capacitor symbol at one end of the diode that represents the variable capacitor characteristics of the varactor diodes. Varactor or varicap diodes are used mainly in radio frequency or rf circuits to provide voltage controlled variable capacitance. Varactor diode working, characteristics and its applications. Varactor diode definition, symbol, construction and. 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. As a result these diodes are also referred to as varicaps, tuning diodes, voltage variable capacitor diodes, parametric diodes and variable capacitor diodes. It is well known that the operation of the pn junction depends on the bias applied which can be either forward or reverse in characteristic. A varactor diode is a pn junction diode that changes its capaci.
Varactor diode construction, working, characteristics, applications. Pdf this paper deals with the largesignal analysis of parametric amplification mixing using reverse biased pn junction varactor diodes. A varactor diode is a pn junction diode that is especially operated in reverse biased mode. Lets look into the construction, working of diode, characteristics and applications of varactor. Even though the outcome of the variable capacitance can be shown by the normal pn.
The varactor diode is a pn junction diode whose capacitance is varied by varying the voltage. A varactor diode also known with the names varicap diode, varactor diode, tuning diode is a pn junction diode which acts as a variable capacitor under varying reverse bias voltage across its terminals. The word varicap is originated from the combination of word variable and capacitor. Setting the standard for nearly 30 years, this highly accurate text is supported by strong pedagogy and content that is ideal for new students of this rapidly. Varactor diode definition, symbol, construction and working diode.
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