Shane Nelson wrote:
>
> On Mon, 8 Sep 1997, Lawrence Lile wrote:
>
> > Famous Quotations from Patz R.  :
> >
> > > I am currently designing a temperature sensor using a 16C54 and the
> > > AN512. This involves charging a capacitor via two resistors
>
>  <snip>
>
> > I've used it on several projects.  I had a lot of problems with drift
> > and noise.  I had one project that wouild hold a temperature setpoint
> > then slowly drift off by 25 C per hour.   One project ended up
> > hinging on a good enough averaging and noise immunity algorithm - any
> > ONE measurement was completely unreliable.
>
> I'm also trying to use this method on a project and am having the
> same types of problems.  Lots of drift, and maybe some noise. Not
> sure what's causing it or how to cancel it's effect.   The
> thought crossed my mind to take like, 10 measurements for every
> display update, and average them out.  Haven't gotten around to
> doing this yet though, because I don't think it will help the
> drift problem. Only the noise. If anyone has an algorithim that's
> already working I'd love to see it :)
>
> I'm also investigating the posibility of using a PIC with an a/d
> on it and doing it that way. I wonder if the a/d will have the
> same problems though?
>
> -Shane.

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