In a DC circuit, a capacitor is equivalent to an open circuit. A capacitor is a component that can store charge and is also one of the most commonly used electronic components. In the circuit, the capacitor has the following functions:

**Coupling:**The capacitor used in the coupling circuit is called the coupling capacitor. This type of capacitor circuit is widely used in the resistance-capacitance coupling amplifier and other capacitive coupling circuits to isolate the direct current from the alternating current.

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

**Decoupling:**The capacitor used in the decoupling circuit is called the decoupling capacitor. This capacitor circuit is used in the DC voltage supply circuit of the multi-stage amplifier. The decoupling capacitor eliminates harmful low-frequency AC between each stage amplifier. Joint.

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**ncy vibration elimination:**The capacitor used in the high-frequency vibration elimination circuit is called a vibration-eliminating capacitor. In the audio negative feedback amplifier, in order to eliminate the possible high-frequency self-excitation phenomenon.

**Resonance:**The capacitor used in the LC resonant circuit is called a resonant capacitor, which is required in both the LC parallel and series resonant circuits.

**Bypass:**The capacitor used in the bypass is called the bypass capacitor. If you need to remove a certain segment of the signal from the signal in the circuit, you can use a bypass capacitor circuit.

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

**Timing:**The capacitor used in the timing circuit is called the timing capacitor. Timing capacitor circuits are used in circuits that need to be charged and discharged through capacitors for practical control. The capacitors play a role in controlling the size of the time constant.

**Integration:**The capacitor used in the integration circuit is called the integration capacitance. In the synchronous separation circuit of the electric potential field scanning, using this integrating capacitor circuit, the field synchronization signal can be extracted from the field coincidence synchronization signal.

**Differential:**The capacitor used in the differential circuit is called the differential capacitor. In order to obtain the tip trigger signal in the trigger circuit, this differential capacitor circuit is used to obtain the tip pulse trigger signal from various signals.

**Compensation:**The capacitor used in the compensation circuit is called the compensation capacitor. In the bass compensation circuit of the deck, this low-frequency compensation capacitor circuit is used to boost the low-frequency signal in the playback signal. In addition, there are high-Frequency compensation single capacitor circuits.

**Frequency division:**The capacitor in the frequency division circuit is called the frequency division capacitor. In the speaker frequency division circuit of the speaker, the frequency division capacitor circuit is used to make the high-frequency speaker work in the high-frequency range, and the mid-frequency speaker works in the mid-frequency band. The low-frequency speaker works in the low-frequency range.