AVR-Chat

> > What type/size capacitor do you have on the power pin
> > of the ad595? It needs to be 10uF or better and not
> > tantalum based. Same goes for the avr uC.]

>47uF aluminun and 100nF ceramic SMD mounted right on the
>power pins on both chips. I also tried to put a huge
>4700 uF on the CPU to see if that was the problem.
>It made no difference at all.

Be careful about the "Bigger is better!" theory of capacitors. Keep 
in mind that electrolytic capacitors are coiled aluminum foil and 
have inductance. Remove all electrolytic capacitors from the 5V side 
of your regulator. Use 1 tantalum cap of 2.2uF to 10uF on the output 
of your regulator and one .1uF ceramic cap across the power pins of 
each IC. Check schematics in any electronic magazine or take apart 
any 8 bit computer and see what the industry standard is. Throwing 
10uF caps randomly into a circuit is the electronic equivalent of 
bloodletting and will cause more harm than good.