DIODO VARICAP. Los diodos varactores o varicap han sido diseñados de manera que su funcionamiento sea similar al de un capacitor y. Diodo Varicap. JC. Johan Cordoba Hoyos. Updated 9 March Transcript. Referencias de imagenes en orden de aparicion y Bibliografia. All following user names refer to dia. Kormoran 87× × ( bytes) Simbolo circuitale di un diodo varicap.
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A third circuit, at top right in diagram, uses two series-connected varicaps and separate DC and AC signal ground connections.
This file contains additional information such as Exif metadata which may have been added by the digital camera, scanner, or software program used to create or digitize it. Higher-current devices with greater junction area tend to possess higher capacitance.
These circuit configurations are quite common in television tuners and electronically tuned broadcast AM and FM receivers, as well as other communications equipment and industrial equipment. The amount of reverse bias controls the thickness of the depletion zone and therefore the varactor’s junction capacitance. These types were — vzricap still are — extensively used in television tuners, whose faricap carrier frequencies require only small changes in capacitance. The DC ground is shown as a traditional ground symbol, and the AC ground as an open triangle.
All diodes exhibit this variable junction capacitance, but varactors are manufactured to exploit the effect and increase the capacitance variation. I, the copyright holder of this work, hereby publish it under the following license:. They are often dioeo in pairs to switch between two different RF sources such as the VHF and UHF bands in a television tuner by supplying them with complementary bias voltages.
If the file has been modified from its original state, some details such as the timestamp may not fully reflect those of the original file. In some applications, such as harmonic multiplicationa large signal amplitude alternating voltage is applied across a varicap to deliberately vary the capacitance at signal rate to generate higher harmonics, which are extracted through filtering.
In other projects Wikimedia Commons. Generally the use of a varicap diode in a circuit requires connecting it to a tuned circuitusually in parallel with any existing capacitance or inductance. In electronicsa varicap diodevaractor diodevariable capacitance diodevariable reactance diode or tuning diode is a type of diode designed to exploit the voltage-dependent capacitance of a reverse-biased p—n junction.
See lower left circuit in diagram. Although they are still slightly conductive to the RF path, the attenuation they introduce decreases the unwanted signal to an acceptably low level. This page was last edited on 13 Novemberat This section does not cite any sources.
Varicap – Wikipedia
The following other wikis use this file: This helps explain the different names for the device as it came into use. September Learn how varciap when to remove this template message. This work has been released into the public domain by its author, Example at dildo [[:: In case this is not legally possible: Capacitor types Ceramic resonator Crystal oscillator Inductor Parametron Relay reed relay mercury switch.
Phase-locked loops are used for the frequency synthesizers that tune many radios, television setsand cellular telephones. Please help improve this section by adding citations to reliable sources. Internal structure of a varicap. The three leaded devices depicted at the top of the page variczp generally two common cathode connected varicaps in a single package.
All following user names refer to it.
This licensing tag was added to this file as part of the GFDL licensing update. The Art of Linear Electronics. The timestamp is only as accurate as the clock in the camera, and it may be completely wrong. The figure shows an example of a vsricap section of a varactor with the depletion layer formed of a p—n junction.
Summary [ edit ] Description Diodo Varicap. Date and time of digitizing lun 5 lug Varactors are operated in a reverse-biased state, so no DC current flows through the device.
Sometimes, with very high-Q tuned circuits, an inductor baricap placed in series with the resistor to increase the source impedance of the control voltage so as not to load the tuned circuit and decrease its Q.