1. Different definitions
Thin film capacitor: thin film capacitor is a kind of capacitor with metal foil as electrode, which is overlapped with polyethylene, polypropylene, polystyrene or polycarbonate and other plastic films from both ends, and then wound into a cylindrical structure.
Electrolytic capacitor: electrolytic capacitor is a kind of capacitor. The metal foil is the positive electrode (aluminum or tantalum). The oxide film (aluminum oxide or tantalum pentoxide) close to the positive electrode is the dielectric. The cathode is composed of conductive materials, electrolyte (electrolyte can be liquid or solid) and other materials. Because the electrolyte is the main part of the cathode, electrolytic capacitor is named.
At the same time, the positive and negative of the electrolytic capacitor cannot be wrongly connected. Aluminum electrolytic capacitors can be divided into four categories: lead type aluminum electrolytic capacitors; Oxhorn type aluminum electrolytic capacitor; Bolt type aluminum electrolytic capacitor; Solid aluminum electrolytic capacitor.
2. Different types
Film capacitance: according to the type of plastic film, it can also be divided into: polyethylene capacitance (also called Mylar capacitance), polypropylene capacitance (also called PP capacitance), polystyrene capacitance (also called PS capacitance) and polycarbonate capacitance.
Its structure is the same as the paper dielectric capacitor, and the medium is polyester or polystyrene. Polyester film capacitor, with high dielectric constant, small volume, large capacity and good stability, is suitable for bypass capacitor. Polystyrene film capacitor has low dielectric loss, high insulation resistance, but high temperature coefficient, and can be used in high-frequency circuits.
Film capacitors can be divided into two categories: DC film capacitors and AC film capacitors: DC film capacitors refer to film capacitors working in circuits powered by DC power, which can be divided into four categories: general type, suppression of power electromagnetic interference type, pulse type and precision type;
AC film capacitor refers to the film capacitor working in the circuit powered by AC power supply, which is divided into motor starting operation, power factor compensation, etc. according to function.
Electrolytic capacitor: lead type aluminum electrolytic capacitor; Oxhorn type aluminum electrolytic capacitor; Bolt type aluminum electrolytic capacitor; Solid aluminum electrolytic capacitor.
3. Different characteristics
Thin film capacitor: thin film capacitor is a capacitor with excellent performance due to its many excellent characteristics. Its main characteristics are as follows: non-polarity, high insulation impedance, excellent frequency characteristics (wide frequency response), and small dielectric loss. Based on the above advantages, thin film capacitors are widely used in analog circuits.
Especially in the signal interconnection part, capacitors with good frequency characteristics and extremely low dielectric loss must be used to ensure that there is not too much distortion when the signal is transmitted. Among all plastic film capacitors, polypropylene (PP) and polystyrene (PS) capacitors have the most prominent characteristics. Of course, the price of these two kinds of capacitors is also relatively high.
However, in order to improve the sound quality of audio equipment, the parts and materials used have become more and more advanced, and the price is not the most important factor to consider, so the frequency and quantity of PP capacitor and PS capacitor used in audio equipment are also increasing.
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Guocan Electronics produces, develops, designs and sells film capacitors, DC film capacitors, power electronic capacitors, AC motor capacitors, axial capacitors, resistance capacitors, suppression of power electromagnetic interference, chip capacitors,