varactor diode

electronics

Also known as: variable reactor

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Last updated

July 14, 2026

Quick Summary

A varactor diode, also known as a variable reactor or varicap diode, is a semiconductor device that functions as a capacitor whose capacitance changes with applied voltage. It is a type of p-n junction diode specifically designed with an impurity profile that makes its capacitance highly sensitive to reverse-biased voltage.12

Varactor diodes are crucial components in electronics, particularly in applications requiring voltage-controlled tuning. They are widely used in:
* Parametric amplification
* Harmonic generation
* Mixing
* Detection
* Voltage-variable tuning applications2

These diodes are essential throughout the radio and television industries for signal transmission.3

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semiconductor device
Varactor diode
The varactor (variable reactor) is a device whose reactance can be varied in a controlled manner with a bias voltage. It is a p-n junction with a special impurity profile, and its capacitance variation is very sensitive to reverse-biased voltage. Varactors are widely…
Read More
The varactor (variable reactor) is a device whose reactance can be varied in a controlled manner with a bias voltage. It is a p-n junction with a special impurity profile, and its capacitance variation is very sensitive to reverse-biased voltage. Varactors are widely…
Read More