- A pn-junction diode operated with reverse bias, so that it functions as a voltage-dependent capacitor. The p and n regions each act as the plates, with the depletion layer serving as the dielectric. Its capacitance varies as a function of its applied voltage, and is used, for instance, for electronic tuning. It is an acronym for variable reactor. Also called varactor diode, varicap, varicap diode, variable-capacitance diode, or voltage-variable capacitor.
- synonymvariable reactor
- synonymvariable-capacitance diode
- synonymvaricap diode
- synonymvoltage-variable capacitor