Common problem
The main role of electrolytic capacitors.
Electrolytic capacitor is also a kind of capacitor, there are positive and negative points, it is characterized by large capacity, do you know what the role of electrolytic capacitor? Here is a small introduction for you, usually play these six roles, let's go together to understand it.
Introduction of electrolytic capacitor.
Electrolytic capacitor is a kind of capacitor, the metal foil is the positive pole (aluminum or tantalum), the oxide film (aluminum oxide or tantalum pentoxide) which is close to the positive pole is the dielectric, the cathode is composed of conductive material, electrolyte (electrolyte can be liquid or solid) and other materials together, because electrolyte is the main part of the cathode, electrolytic capacitor is thus named. At the same time, the positive and negative electrolytic capacitors cannot be connected wrongly. Aluminum electrolytic capacitors can be divided into four categories: lead type aluminum electrolytic capacitors; bullhorn type aluminum electrolytic capacitors; bolt type aluminum electrolytic capacitors; and solid state aluminum electrolytic capacitors.
The role of electrolytic capacitors.
The first role is to be placed inside the circuit to block the DC, which can be used as a DC switch, that is, the DC comes to be approximated as an open circuit, and the AC comes to be approximated as a closed circuit.
The second role is in the switching power supply circuit design, rectifier circuit out, to access a large-capacity electrolytic capacitors, can make the pulsating DC voltage becomes very stable, the harmful AC components are introduced to the earth.
The third role is the role of mutual coupling. Generally connected to the low-frequency signal transmission and amplification between the two stages of the circuit, can prevent the two static operating points interfere with each other, allowing only the AC signal through.
The fourth role is the role of bypass, to provide a low-impedance circuit for some components in the AC circuit.
The fifth role is the role of stored energy, used in specific situations to release the required current.
The sixth role is the role of adjusting the resonant frequency, such as radio circuits, LC crystal circuits.
Characteristics of electrolytic capacitors.
1. the capacity per unit volume is very large, tens to hundreds of times larger than other kinds of capacitors.
2. the rated capacity can be very large, it can easily be tens of thousands of μf or even several f (but it can't be compared with double layer capacitor). 3. the price is higher than other kinds of capacitors with high voltage.
3. The price is overwhelmingly superior to other types of capacitors because the materials used in electrolytic capacitors are common industrial materials, such as aluminum. The equipment for manufacturing electrolytic capacitors is also common industrial equipment, which can be mass-produced and the cost is relatively low.
The above is the introduction of the role of electrolytic capacitors, do you understand now? Electrolytic capacitors are needed in many places, so with the development of technology, the performance of electrolytic capacitors will be better and better.