On Sun, 09 Dec 2012 13:59:13 -0800, the renowned Jeff Liebermann
wrote:


Yep. The electrolyte in 85C caps boils at about 125C, while the 105C
caps boil at about 190C. Other than that, there's not much difference
between the two types. If you can keep the temperature low, 85C works
just as well as 105C. Above 100C(?), the 85C cap develop increased
leakage current, while the 105C doesn't leak.

They'll both work okay at, say 40°C, but according to the formulas,
_all_ things being equal, 105°C caps should last about four times
longer than 85°C caps.

That's why I spec them, not because I think it will ever get to 85°C.
They don't cost that much more, are not that much bigger and have a
plethora of sources. I also like to have a generous margin on the WV
(which one of the forumulas indicates would have an effect on the
life- it tends to make the cap a bit bigger and helps dissipate power
from the ESR). In both cases, I'm not sure what the real effect on
life is, but I have had not had to revisit the choices, which is good.


Best regards,
Spehro Pefhany
--
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