What are the main functions of capacitance and inductance in the circuit?

Capacitance: Capacitor is a kind of electric charge that can be stored. Inductance: It mainly plays the role of filtering, oscillation, delay, notch, etc. It also has the functions of filtering signal, filtering noise, stabilizing current and suppressing electromagnetic wave interference.

capacitance:

Capacitors, usually abbreviated as their ability to hold charges, are capacitors, represented by the letter C.

Definition 1: Capacitor, as the name implies, is a'container for holding electricity', a device that holds electric charge. English name: capacitor. Capacitors are one of the most widely used electronic components in electronic equipment. They are widely used in circuits such as blocking, coupling, bypassing, filtering, tuning loops, energy conversion, and control.

Definition 2: Capacitor, any two insulated and very close conductors (including wires) form a capacitor.

●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 block DC and AC.

●Filtering: The capacitor used in the filter circuit is called the filter capacitor. This capacitor circuit is used in the power supply filter and various filter circuits. The filter capacitor removes 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 the harmful low-frequency cross-connection between each amplifier.

●High frequency damping: the capacitor used in the high frequency damping circuit is called the high frequency damping capacitor. In the audio negative feedback amplifier, in order to eliminate the high frequency self-excitation that may occur, the capacitor circuit is used to eliminate Possible high-frequency howling from the amplifier.

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

●Bypass: The capacitor used in the bypass circuit is called the bypass capacitor. If you need to remove the signal of a certain frequency band from the signal in the circuit, you can use the bypass capacitor circuit. Depending on the frequency of the removed signal, there is a full frequency domain. (All AC signals) bypass capacitor circuit and high frequency bypass capacitor circuit.

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

● Timing: The capacitor used in the timing circuit is called the timing capacitor. Timing capacitor circuits are used in circuits that require time control through capacitor charging and discharging, and 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 vertical synchronization signal can be taken out from the field composite synchronization signal.

●Differential: The capacitor used in the differential circuit is called the differential capacitor. In order to obtain the peak trigger signal in the trigger circuit, this differential capacitor circuit is used to obtain the peak pulse trigger signal from various (mainly rectangular pulse) 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 enhance the low-frequency signal in the playback signal. In addition, there are high-frequency compensation capacitors. Circuit.

Bootstrap: The capacitor used in the bootstrap circuit is called the bootstrap capacitor. The commonly used OTL power amplifier output stage circuit uses this bootstrap capacitor circuit to increase the positive half-cycle amplitude of the signal by a small amount of positive feedback.

● 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 loudspeaker work in the high frequency band, and the mid frequency loudspeaker works in the middle frequency band, and the low frequency The loudspeaker works in the low frequency range.

●Load capacitance: refers to the effective external capacitance that determines the resonant frequency of the load together with the quartz crystal resonator. Commonly used standard values ​​of load capacitance are 16pF, 20pF, 30pF, 50pF and 100pF. The load capacitance can be adjusted appropriately according to the specific situation. Generally, the working frequency of the resonator can be adjusted to the nominal value through adjustment.

inductance:

The most common role of inductance in a circuit is to form an LC filter circuit together with a capacitor. Capacitors have the characteristics of "blocking DC and blocking AC", while inductors have the function of "blocking DC and blocking AC". If the direct current accompanied by many interference signals is passed through the LC filter circuit, the AC interference signal will be consumed by the inductance into heat; when the pure DC current passes through the inductor, the AC interference signal in it will also become magnetic induction. And heat energy, the higher frequency is most likely to be impedance by the inductance, which can suppress the higher frequency interference signal.

Inductors have the characteristics of preventing alternating current from passing through and allowing direct current to pass smoothly. The higher the frequency, the greater the coil impedance. Therefore, the main function of the inductor is to isolate and filter AC signals or form a resonant circuit with capacitors and resistors.