[CAD_CAM_EDM_DRO] PID primer, was Dedicated mb for PID

I just looked at the pdf for the LM628 on National's site. While intended
as a datasheet it is nonetheless the best primer on PID loops I've read to
date.

Now I see what the sampling interval for D and the integration limit are
for - they keep the filter from blowing up. Still, they are simple to
implement. 10KHz should be easy in any compiled language.

Go here if you want a primer on PID.
http://www.national.com/ds/LM/LM628.pdf

Doug

----- Original Message -----
From: Les Watts <leswatts@...>

> Yup that is pretty much it. We map it to the z plane for discrete systems.
> Also note that sD blows up with high frequencies; I/s blows up approaching
> DC (s=0) so a practical system has to have a few more terms in it.