I read an electronic magazine in which there is a report on what are the differences between Mica capacitors general capacitors. After reading, I became interested in Mica capacitors that I have never seen before. So I searched some related materials and information about this topic from google. Today I come to this forum to turn to you to discuss my understandings are appropriate.
Here are my personal understandings:
Mica capacitors are made of metal foil or silver plate on the mica to do the electrode plate, plate and mica layer after layer, and then die-casting in the bakelite powder or sealed in the epoxy resin made. It is characterized by small dielectric loss, large insulation resistance, the temperature coefficient is small, suitable for high-frequency circuits. Mica capacitors are widely used in applications where the stability and reliability of capacitors are high. Mica capacitor small size, light weight, solid structure, easy installation, stable performance. Available performance is excellent in radio equipment, precision electronic equipment, modern communications equipment and equipment, radio, amplifier, TV.
As the mica material has excellent electrical and mechanical properties, so that the mica capacitor itself inductance and leakage loss is very small, with a wide range of voltage, high reliability, stable performance, high precision and other advantages. Particularly suitable for use in high-frequency oscillation circuit , High-precision operation amplification, filter circuit and other occasions.
Mica capacitor as a non-polar capacitor, compared with the general non-polar capacitor has a great advantage, personally think that it is the best of a non-polar capacitor. Capacity is generally between 4.7-51000pF, the accuracy can reach ± 0.01 % - ± 0.03, which is difficult to achieve the general capacitor (compared to some low - frequency ceramic capacitors and some aluminum electrolytic capacitors, the value of the accuracy is generally ± 20, up to ± 50%.
Mica capacitors have high electrical insulation, better transparency, excellent peelability, higher chemical stability, better reduction and high temperature conditions to maintain the excellent physical and chemical properties, and thus It is mainly used as a very important insulating material widely used in electronics, electrical, telecommunications, electrical, aviation, transportation, instrumentation, metallurgy, building materials, light industry and other industrial sectors, as well as national defense and cutting-edge industries. Since the 1970s, the use of mica in the insulation support material and dielectric material of capacitors and motors has been replaced by mica paper made from crushed mica, and the vast majority of communication tubes have been replaced by semiconductor integrated circuits , Causing a fundamental change in the consumption structure, so the demand for mica is significantly reduced, while the demand for broken mica growing. With the development of science and technology, moss mineral in recent years in the building materials, geological exploration, lubrication, paint, food, cosmetics and other applications continue to expand, broken mica and sericite mineral raw materials will have broad application prospects.
What are the differences between Mica capacitors and general capacitors?
Mica capacitor temperature coefficient is small, generally can reach 1 \* 10 ^ (–6) / ℃ or less, than the average organic film capacitors (such as polyester capacitors) is much better, compared with the ceramic capacitor is more obvious advantages.
Mica capacitors can work in high temperature environments, the maximum ambient temperature can reach 460 ℃, far more than the general ceramic capacitors, and the general aluminum electrolytic capacitors can only work at 105 ℃. And long-term storage capacity of the mica capacitance changes between 0.01% –0.02%, also better than the average capacitor.
If you want to do high-quality, high-precision, high stability of the analog circuit, mica capacitor is the only choice. In the high-end circuits (such as high-end Hi-Fi audio), the basic use are also mica capacitors.
As the mica capacitor production process is more complex, costly, bulky, limited capacity, so the price in the market is also higher than the average capacitor.
Ps: Excuse me if I was wrong in words or expressions as I am a green hand in the field of Mica capacitors. I need continual learnings.
What is your idea ? Do you agree with my ideas ? Any of your ideas would be highly appreciated.
May someone would like to help ?
thanks in advance
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