[TCML] ESR ESL figures in caps

[Bert Hickman]

Hi Chris,

In theory, when paralleling N capacitors, overall ESR and ESL will be 
divided by N (similar to paralleling discrete resistor or inductors). 
The capacitance will be multiplied by N. So, the equivalent ESR and ESL 
will be the individual ESR and ESL divided by the number you have in 
parallel.

However, in practice, what you ACTUALLY obtain will be a function of 
your physical layout and interconnection scheme. For reasonably 
interconnection schemes, both ESR and ESL will still be significantly 
lower than that of a single cap, but not as low as theory predicts.

Bert
-- 
***************************************************
We specialize in UNIQUE items! Coins shrunk by huge
magnetic fields, Lichtenberg Figures (our "Captured
Lightning") and out of print technical Books. Visit
Stoneridge Engineering at http://www.teslamania.com
***************************************************

Chris Swinson wrote:
> Hi all,
> 
> I am looking at a cap, 5mR ESR, 15uH ESL.
> 
> Now if I parallel a load of these, then are the ESR figures multiplied 
> in parallel like regular resistors would add up. For example 10caps 5mR 
> each = 10x5=25mR total ?
> 
> If I remember right (probably not) , inductors in series multiply, and 
> in parallel half...
> 
> so Do I have it right in saying ESR figures multiply, and ESL divide ?
> 
> It could be the total figures may be the same as one cap, though not 
> sure hence the question!
> 
> I am having problems with simulating this, as going from 1 cap, to 2 
> caps (half capacitance) they seem to operate different, like one starts 
> to discharge faster, but speeds up as it drops past 50%, and when you 
> swap the caps, the opposite happens, so overall its hard to judge.
> 
> Cheers!
> Chris
> 
> 
> _______________________________________________
> Tesla mailing list
> Tesla at www.pupman.com
> http://www.pupman.com/mailman/listinfo/tesla
>