Re: amp ratings for MMCs?

[Terry Fritz <twftesla-at-uswest-dot-net>]

Hi David,

See the following if you have not already:

http://users.better-dot-org/tfritz/MMCPower4.html
http://users.better-dot-org/tfritz/site/programs/MMCCALC2.ZIP

This will tell you how hot they get and such.  In general you do not need to
add anything to these equations since the manufacturers already "pad" there
numbers about 50%.  If you use high current poly caps, the dV/dT rating will be
fine.  The RMS current is much more important IMHO.

Cheers,

        Terry

At 04:09 PM 7/27/00 -0400, you wrote: 
>
> Hi everyone,
> Apologies for my elementary question, but -- I have heard before that
> properly rating an MMC for amps is at least as important as the voltage
> rating, but wherever I read about MMC caps amps seems to be an under
> addressed issue.  I know you can use the dV/dT or V/usec ratings to determine
> a cap's rms current capabilities but whenever I "try" to use it, I come out
> with some weird value that doesn't make any sense.  Can someone else please
> make some sense out of these ratings forme?
>  
> And one more thing while I have your attention :^), can you overamp an MMC or
> is it wise to overrate the MMC amp rating?
>  
> Many thanks to all                                             Dave