[Cryptech Tech] User auditable hardware entropy source/random number generator

[Fredrik Thulin]

On Monday, July 14, 2014 09:54:27 AM Benedikt Stockebrand wrote:
...
> Fredrik Thulin <fredrik at thulin.net> writes:
> > Hmm? You mean you are using an off the shelf charge pump circuit rather
> > than a diodes-and-caps voltage doubler, like the Dickson doubler [1] [2]?
> >
> Not a charge pump but a boost converter---USB +5V may not be stable
> enough for a charge pump.  I use an MC34063, with the externals chosen
> such that it works until the brownout detector in the Atmel triggers
> anyway.
> 
> But this isn't cast in stone; this stuff is modular enough I can use
> whatever suitable source I can find, and I've already used others.  If
> you have a better idea, please let me know.

What is a suitable source? Are you saying that the generated entropy would 
suffer from a somewhat unstable power line?

I've seen USB powered discrete component charge pumps used in this application 
before, but I realize that doesn't mean it's a good idea =).

/Fredrik