Ken Weitzel writes:

chibitul wrote:

Hi,
I need an electrolytic capacitor, 100V/35uF. I don't have one right
now... can I use two in series, let's say 50V/68uF? The equivalent
capacity should be 34uF, and since they are in series, the maximum
voltage 100V.
Thanks

Hi Chibutul...

I think I'd much sooner see two 17's in series...

OK, we know you meant parallel.

However, two caps in series isn't nearly as efficient
so while you're rounding, round up.

Which may (probably will) leave you with linearity problems,
so were it my set I'd keep on looking for a 34 at greater
than 100 volts.

It's not the efficiency or linearity that would be the main issue
with capacitors in series. The problem is that if the leakage
resistances and capacitances are not the same, the voltage across
the two caps with not be equal. So, use a higher voltage to be
on the safe side if the application really requires close to
the working voltage.

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