[Soekris] Soekris-tech Digest, Vol 35, Issue 7

[Dr Bruce Griffiths]

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> Today's Topics:
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>    1. Solid state capacitors (Mats Lundqvist)
>    2. Re: Solid state capacitors (Poul-Henning Kamp)
>    3. Re: Solid state capacitors (Mats Lundqvist)
>    4. Re: Solid state capacitors (Stanislav Meduna)
>    5. Re: Solid state capacitors (Poul-Henning Kamp)
>    6. Re: Solid state capacitors (Poul-Henning Kamp)
>    7. Re: Solid state capacitors (Mats Lundqvist)
>    8. Re: Solid state capacitors (Poul-Henning Kamp)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Thu, 11 Jan 2007 16:41:35 +0100
> From: "Mats Lundqvist" <mats.lundqvist at gmail.com>
> Subject: [Soekris] Solid state capacitors
> To: soekris-tech at lists.soekris.com
> Message-ID:
> 	<45d561bc0701110741p3a4cc288ia508285848c5b5eb at mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Hello
>
> Does Soekris plan on offering a product using solid state capacitors instead
> of electrolytic capacitors (did I spell it right?).
>
> I have a lot of interest in deploying a soekris in an environment that's
> below freezing point, now I have one that's about to be deployed, but uses a
> heating circuit inside the casing to warm things up when the Swedish winter
> weather sets in...
>
> I imagine the rest of the circuits on the board would do just fine in cold
> weather since they are all solid state.
>
> Cheers!
> Mats Lundqvist
>
>   

The capacitance of an electrolytic capacitor drops dramatically when the 
electrolyte freezes.
The ESR may also increase to around 30x the room temperature (25C) value 
at -40C.
The ESR of solid aluminium capacitors is much less temperature dependent 
and the capacitance is less temperature dependent.

Bruce