When do you use capacitors and electrolytic capacitors?

The capacitor has the function of AC blocking DC. The capacitive reactance of the capacitor is inversely proportional to the frequency. The electrolytic capacitor generally has a large capacity. It is generally used in low frequency circuits.

Capacitors are important components of the forward power factor in the power system; they are the primary components in the electronic circuit for obtaining oscillation, filtering, phase shifting, bypassing, coupling, and the like.

1. Filtering function, in the power supply circuit, the rectifier circuit turns the alternating current into a pulsating direct current, and after the rectifier circuit is connected to a larger capacity electrolytic capacitor, using its charge and discharge characteristics, the rectified pulsating DC voltage becomes Relatively stable DC voltage. In practice, in order to prevent the power supply voltage of each part of the circuit from being changed due to load changes, there are usually tens to hundreds of micro-electrode electrolytic capacitors at the output end of the power supply and the power input end of the load. Because large-capacity electrolytic capacitors generally have a certain inductance, the high-frequency and pulse annoyance signals cannot be effectively filtered out, so a capacitor with a capacity of 0.001--0.lpF is connected in parallel at both ends to filter out the high-frequency. And pulse annoyance.

2. Coupling effect: In the process of transmission and expansion of low-frequency signals, in order to prevent the static working points of the two-stage circuit from interacting with each other, capacitor coupling is often used. In order to prevent the low frequency component of the signal from being lost too much, the electrolytic capacitor with a large capacity is generally selected.