The basic function of capacitors is charging and discharging, but many circuit phenomena extended from this basic charging and discharging function make capacitors have various uses. For example, in electric motors, we use them to generate phase shift; in photo flash In electronic circuits, capacitors have different properties and uses, although there are also distinct differences, but their functions are all from charging and discharging.

1. Coupling: The capacitor used in the coupling circuit is called a coupling capacitor, which is widely used in resistance-capacitance coupling amplifiers and other capacitive coupling circuits to isolate DC and AC.

2. Filtering: The capacitor used in the filter circuit is called a filter capacitor. This capacitor circuit is used in power supply filtering and various filter circuits. The filter capacitor removes the signal in a certain frequency band from the total signal.

3. Decoupling: The capacitor used in the decoupling circuit is called the decoupling capacitor, which is used in the DC voltage supply circuit of the multi-stage amplifier. The decoupling capacitor eliminates the harmful low-frequency cross-connection between the amplifiers of each stage.

4. High-frequency vibration elimination: The capacitor used in the high-frequency vibration elimination circuit is called a high-frequency vibration elimination capacitor. Eliminates high frequency howling that can occur with the amplifier.

5. Resonance: Capacitors used in LC resonant circuits are called resonant capacitors, which are required in both LC parallel and series resonant circuits.

6. Bypass: The capacitor used in the bypass circuit is called the bypass capacitor. If the signal in a certain frequency band needs to be removed from the signal in the circuit, the bypass capacitor circuit can be used. According to the frequency of the removed signal, there are full frequency Domain (all AC signals) bypass capacitor circuit and high frequency bypass capacitor circuit.

7. Neutralization: The capacitor used in the neutralization circuit is called the neutralization capacitor. In radio high-frequency and intermediate-frequency amplifiers, and television high-frequency amplifiers, this neutralizing capacitor circuit is used to eliminate self-excitation.