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Two or more capacitors are rarely deliberately connected in series in real circuits, but it can be useful to connect capacitors in parallel to obtain a very large capacitance, for example to smooth a power supply.
Yes, you can. But always use also parallel resistors! Why? The working voltage of a series combination of identical capacitors is equal to the sum of voltage ratings of individual capacitors. This simple relationship only applies if the voltage ratings are equal as well as the capacitances. However, the division of DC voltage between the capacitors is dominated by the leakage resistance of the capacitors, rather than their capacitances, and this has considerable variation. To counter this equalising resistors may be placed in parallel with each capacitor which effectively add to the leakage current. The value of resistor chosen (perhaps a few megohms) is as large as possible, but low enough to ensure that the capacitor leakage current is insignificant compared to the current through the resistor.
This is from Wikipedia ...
And - as Izeek wrote - the "capacitance will 0.5 of initial amount"
Hope this helps
zuisti
I do not think it's a good idea to place resistors in paralell. Aplying resistior in paralell to capacitor will degrade DC leackage and it's quality factor. Because of the circuit resistance decreace with increasing of number of the same resistors in paralell proportional to it's quantity. Also you you can not use this circuit for AC decoupling, for example - gate decoupling in FET-based amplifier.
Unfortunately, you need the resistors to balance the voltage across the caps. If you leave them off, and one cap has more leakage current across it than the other, then that cap will have 5 volts across it, and the other one 45 volts across it. This is a very common technique in high voltage power supplies.
In most RF applications, if the resistors are greater than 1K, they are relatively transparent to the RF signal.
Of course, this only works well when the 2 series caps are mounted in shunt. If you were trying to use the 2 series caps in series as a DC block, adding the resistors would of course negate the reason for the capacitor in the first place.
Caps shouldn’t be exposed to voltages higher then their rating ..
The low-voltage capacitors are really low-voltage ..
If your application operates close to 50V I would go for something like 63V++ ..
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