The first characteristic of SMDcharacteristics electrolytic capacitors : the capacitance per unit volume is very large, which is tens to hundreds of times larger than other types of capacitors.

SMDcharacteristics electrolytic capacitors two: rated capacity can be very large, can easily achieve tens of thousands of μf or even a few f (but can not be compared with the electric double layer capacitance).

SMD electrolytic capacitor features three: the price has an overwhelming advantage over other types, because the electrolytic capacitors are composed of ordinary industrial materials, such as aluminum and so on. The equipment for manufacturing electrolytic capacitors is also ordinary industrial equipment, which can be mass-produced at a relatively low cost.

The positive and negative distinctions of chip electrolytic capacitors

1.one is a common chip electrolytic capacitor, which is a cylindrical square shape, and the end marked with “-” is positive; there is also a silver surface-mounted capacitor, which should be aluminum electrolysis. The top is round and the bottom is square, which is very common on the optical drive circuit board. This type of capacitor has a negative end marked with a “-“.

2.Appearance judgment

  • The end marked with a different color from the surface of the capacitor is negative, and the other is positive

3.Multimeter resistance file judgment

  • Connect the two test leads of the resistance file to the two ends of the capacitor, the resistance value will be displayed from small to large, and finally tend to infinity.
    Reverse the test lead and measure again, the resistance value will be displayed from small to large, and finally tend to infinity.
  • When the resistance value increases faster, the positive test lead indicates negative.