> > The spec sheet states a Vdd voltage level below which the processor
should
> > be in reset mode and above which it should be operational. No
requirements
> > are placed on the rise time of Vdd to meet reset conditions.
>
> In theory if they don't say it matters, than it shouldn't.  On the other
> hand, they didn't come right out and give a rise time spec or say that it
is
> allowed to be infinitely slow.  I would consider this spec as "missing"
> rather than interpret it that infinitely slow is OK.  I would talk to the
> manufacturer.  If they are unwilling or unable to guarantee the infinite
> rise time spec and deliver parts to that spec, then you have two choices:
>
> 1 - Use a different part if you can find one.
>
> 2 - Redesign the circuit to guarantee a maximum rise time.
>
> I know you don't like either option, but that's where you're at.

> Olin Lathrop, embedded systems consultant in Littleton Massachusetts

Unfortunately, option (2) is a bit bogus: without a rise time spec you'll
never know if your circuit is fast enough.

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)

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