Hi, All,
Given all the churn in the parts business at the moment, I've been spending an unconscionable amount of time finding suitable replacements for out-of-stock parts. High value ceramic caps are the worst.
Most makers have websites where you can look at the C(V) curves:
AVX: (This one is super clunky--every time you select something it displays a throbber for 5-10 seconds. It does give you soakage models though, which is nice if they're vaguely accurate.)
Cornell Dubilier has a lifetime/temperature calculator,
Kemet Ksim: (about the best)
Kyocera:
Murata SimSurfing (Honourable mention):
Panasonic has downloadable selection tools that don't run under WINE, so I don't know if they're any good:
Taiyo Yuden TY-Compas (Honourable mention):
TDK:
Yageo:
Samsung has some good datasheets that you can get to from e.g. Digikey's product page, but a lot of their products are the pits, e.g. this one, whose capacitance falls off by over 90% at rated voltage:
Others don't seem to, e.g. Johanson, Vishay, and most of the smaller Chinese outfits.
Sure would be nice if everybody had decent datasheets like Samsung's good ones.
Cheers
Phil Hobbs