The vast majority of types of capacitors are non-polar, only the polarity of electrolytic capacitors, electrolytic capacitors, there are very special non-polar electrolytic capacitors. Compared with ordinary capacitors, electrolytic capacitors, large capacity, low price, small size is unmatched by other capacitors, but the electrolytic capacitors are generally polar, and reliability, pressure, temperature, dielectric loss and other indicators are not as good Other capacitors. The so-called non-polar electrolytic capacitors, in fact, will be the same two electrolytic capacitors back-to-back package together. This capacitor loss, low reliability, low voltage, can only be used for a few occasions less demanding.