[sdiy] Potting, was: Discrete OTA

[cheater00 .]

On Sat, Apr 5, 2014 at 12:20 PM, Ingo Debus <igg.debus at t-online.de> wrote:
>
> Am 03.04.2014 um 23:42 schrieb Tom Wiltshire:
>
>> I can see good reasons for something potted being better - more robust, better protection from the environment, more thermally stable and consistent, etc. What are the advantages of "no potting" beyond "repairability" (which should be a once in twenty years thing if it's done right).
>
> Can a potted subcircuit be reflow soldered? If it can't, this would be a major drawback. More and more ICs these days come in LGA or similar packages that cannot be wave soldered let alone hand soldered. Components that cannot be reflow soldered on the same board would add to manufacturing cost significantly.

Yes, it can.

Also, there are potting compounds which are transparent, re-entrant
and self-healing, which means that you can stick a probe through the
compound and it'll shut the hole over a period of time once you're
done. So I don't see potting as a nuisance - but I also don't see the
necessity. More importantly, I don't know how much said compounds
cost.

D.