What is the normal operating range of a varactor diode and its working principle 2

2. Bias state: When an external voltage or current is applied to a varactor diode, an electric field is formed in the capacitor. This electric field will apply a force to the movable plate, causing it to move to a new position. The movement of the activity board will change the effective capacitance value of the capacitor.

3. Change in capacitance value: When the movable plate moves to a new position, the distance between the movable plate and the fixed plate changes. Due to the inverse proportionality between the capacitance value and the distance between the electrodes, the capacitance value will change accordingly. When the movable board approaches the fixed board, the capacitance value increases; When the movable board moves away from the fixed board, the capacitance value decreases.diode

4. Scope: The range of capacitance variation of a varactor diode depends on the electric field strength and the distance between the movable plate and the fixed plate. Usually, the capacitance value of a varactor diode can vary from a few picofarads (pF) to several hundred pF.

The working principle of varactor diode is based on the effect of electric field force on the movable plate. By changing the voltage or current, the magnitude and direction of the electric field force can be altered, thereby controlling the position of the movable plate and the distance between it and the fixed plate. This enables varactor diodes to be used as variable capacitors in capacitor circuits to meet different circuit requirements.