The varactor also termed to as varicap, is a diode that behaves like a variable capacitor, with the PN junction working like the dielectric and plates of a common capacitor. Because of this, the symbol of the varactor is as shown below:
A varactor diode employs a PN junction in reverse bias and has a structure such that the capacitance of the diode varies with the reverse voltage. A voltage controlled capacitance is useful in tuning applications. The typical capacitance values are small, in the order of picofarads.
The figure below shows a typical tuning circuit where the DC voltage control Vc changes the capacitance of the varactor to form a resonant circuit.
Varactors are being used to replace the old variable capacitor tuning circuits as in television tuners.
Also read: Optoelectronics
Industrial measurement and control processes employ standard process signals that are used throughout all the…
The integration of advanced technologies in security systems has become imperative for ensuring safety and…
Power quality may be affected by a number of issues. Our discussion in this article…
Power quality has become an important issue to electricity consumers at all levels of consumption.…
The importance of printed circuit board (PCB) technology has escalated throughout the years with the…
One of the key challenges in measuring the electrical current in high voltage, high power…
