Electrolytic capacitors are capacitors made with an oxide film formed by electrolysis as the medium. Aluminum electrolytic capacitors are made with high-purity aluminum as the anode and ethylene glycol, glycerol, boron, and ammonia as the electrolyte slurry. Due to the fact that the dielectric film of electrolytic capacitors can be made very thin, they can be made into small volume and large capacity capacitors, which are the main components of large capacity capacitors. However, electrolytic capacitors have many drawbacks, such as poor frequency well and temperature characteristics, high leakage current, and dielectric loss. In addition, when the polarity is reversed or the voltage applied at both ends exceeds the specification, its safety will be compromised, and the electrolyte will vaporize and burst.

Electrolytic capacitors are capacitors made with an oxide film formed by electrolysis as the medium. Aluminum electrolytic capacitors are made with high-purity aluminum as the anode and ethylene glycol, glycerol, boron, and ammonia as the electrolyte slurry. Electrolysis is carried out in an electrolyte, forming an extremely thin alumina film on the surface of aluminum. Due to the fact that the dielectric film of electrolytic capacitors can be made very thin, they can be made into small volume and large capacity capacitors, which are the main components of large capacity capacitors. However, electrolytic capacitors have many drawbacks, such as poor frequency well and temperature characteristics, high leakage current, and dielectric loss. In addition, when the polarity is reversed or the voltage applied at both ends exceeds the specification, its safety will be compromised, and the electrolyte will vaporize and burst (commonly known as breakdown).

The filtering effect of electrolytic capacitors is that in the power supply circuit, the rectifier circuit converts alternating current into pulsating DC, and then the rectifier circuit is connected to a large capacity electrolytic capacitor. By utilizing its charging and discharging characteristics, the pulsating DC voltage after rectification is transformed into a relatively stable DC voltage. In practical applications, in order to prevent the power supply voltage of various parts of the circuit from changing due to load changes, dozens to hundreds of micro electrolytic capacitors are usually connected at the output end of the power supply and the input end of the load. In the transmission and amplification process of low-frequency signals, capacitive coupling is often used to prevent mutual influence between the static working points of the front and rear circuits. To prevent excessive loss of low-frequency components in the signal, large capacity electrolytic capacitors are usually used. The timing function changes the capacitance in the timing circuit, not only changing the charging and discharging time constant, but also completing the cut-off and conduction of the circuit.

 
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