In a way, a capacitor is a little like a battery. Although they work in completely different ways, capacitors and batteries both store electrical energy. Inside the battery, chemical reactions produce electrons on one terminal and absorb electrons on the other terminal. A capacitor is much simpler than a battery, as it can't produce new electrons -- it only stores them.
Electrolytic capacitors are well known to pass a small DC current. How much they pass is a complex function of temperature, capacitance, the age of the capacitor, and the DC voltage across it.
Although I search a lot of related information, I still have a quesition and hope someone can tell me the answer.
Why is that when I use electrolytic capacitors (the cylindrical ones) and measure the end with respect to ground, there is some DC voltage appearing (where in fact it should be 0 volts since capacitor passes only AC signal but blocks DC signal), but when I substituted a non electrolytic capacitor, like tantalum capacitors, they work well. In a simulation program, electrolytic and tantalum shows no difference and they block DC, but in real life, electrolytic fails to function correctly. What's happening?
Electrolytic capacitors are well known to pass a small DC current. How much they pass is a complex function of temperature, capacitance, the age of the capacitor, and the DC voltage across it.
Although I search a lot of related information, I still have a quesition and hope someone can tell me the answer.
Why is that when I use electrolytic capacitors (the cylindrical ones) and measure the end with respect to ground, there is some DC voltage appearing (where in fact it should be 0 volts since capacitor passes only AC signal but blocks DC signal), but when I substituted a non electrolytic capacitor, like tantalum capacitors, they work well. In a simulation program, electrolytic and tantalum shows no difference and they block DC, but in real life, electrolytic fails to function correctly. What's happening?
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