A varactor diode, also known as a varicap diode or voltage-variable capacitor, is a special type of diode that exhibits a varying capacitance with changes in applied voltage. The symbol for a varactor diode consists of a diode symbol with curved lines parallel to the diode’s horizontal line. The curved lines represent the variable capacitance characteristics of the diode. Varactor diodes are commonly used in voltage-controlled oscillators (VCOs), frequency synthesizers, and tuning circuits, where their capacitance can be adjusted by changing the applied voltage, allowing precise control over the resonant frequency or tuning of the circuit.
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The figure below displays Varactor Diode Symbol.
