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Re: [TCML] MMC Caps

The 942 series clearly has better pulse handling rating- dv/dt is an order of magnitude greater for 2kv .15uf
models. Current at 100khz is about 50% greater in the 942 than 940.
I personally have no idea how to translate that into a design suggestion for the man,
because the on line resources are all over the map.

Perhaps someone more knowledgeable than I could write up an MMC calculator that shows peak current (based off of input power supply) so that we could factor this into their calculations, most of us newbs to MMC just assume voltage and capacitance are the only important factors... It should input power supply RMS voltage and current (usually known) MMC capacitor capacitance, MMC capacitor peak current, MMC capacitor peak voltage, number of caps per row, number of rows, cost per capacitor, possibly temperature dissipation and any other important factors on the data sheet, and it should output recommended resonate, LTR and STR values, MMC current capacity/current capacity per string, MMC current draw, MMC voltage total, MMC capacitance, and any other goodies one actually needs to know when seriously constructing one of these to be bullet proof, basically everything you need... It would be awesome if it would give basically a yes it is good in this configuration, or a no it is not, (or even a maybe but use at own risk.) I'd reckon this should be possible on EXCEL but I don't off hand know all the formula required else I would do it, I'm still not working yet so I've nothing better to do... Perhaps primary frequency is also important, I don't even know if that contributes to capacitor failure or not or if it is just a temperature thing, and higher frequency means more heat, though I suppose one could factor temperature dissipation and expected frequency also. It seems to me I had a document that did this but since I can't find it, either it didn't do all that or I was thinking of something else...

Scott Bogard.
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