David,

Why bother with an AVR?
Aren=92t we in a PIClist?
A six pin SOT23-6 device from 10f200 series followed by a MOSFET transistor=
 would take care of the requirements. Low current would not even need the t=
ransistor.

My $0.02,
Jean-Paul
AC9GH=20

On Dec 16, 2013, at 2:45 PM, David VanHorn <microbrix@gmail.com> wrote:

> I agree, the 555 is not well suited to this application with real
> components.  Additionally,  10M resistors are trouble because of humidity
> and pcb contamination issues.   If i had to solve this problem,  i would
> use one of the six pin AVR controllers like the tiny4 running on the
> internal r/c oscillator.   You get four I/O pins and far better control o=
f
> the output.  Not as much drive current and a more narrow power range, but
> that may not be an issue for you.
>=20
> FWIW.
> --=20
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> http://mailman.mit.edu/mailman/listinfo/piclist


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