Quote Originally Posted by The Master View Post
It allows for a variable resistor for calibrating too although i would like to do most of that on the PC.
Yes, you could switch in a voltage reference chip (can't remember the part number for them, but the ones I've used are 4.096v types)...

The outputs im using will output AC and DC Ripple.....
About rectifying the AC. Correct me if im wrong but im pretty sure i should rectify it *after* the potential divider then deal with it in the same way as the DC Ripple.
Yes, otherwise you'll be fighting highs against lows and totally screwing up your readings.

[QUOTE]Im not sure i understand the resistor part. I see how you got the 3rd formula from the first 2 but i dont know about the rest. For a start, what is E? A search on google said "E is the e.m.f. of the power supply (the theoretical maximum voltage across the terminals when no current is flowing)". That doesnt really make any sense to me.[/QUOTE}
E = voltage, electromotive force, as in E=IR. Rarely do I see V=IR although it is used sometimes.

0.1W seems a little small for something thats dealing with 1A at 50V but i see that if theres hardly any resistance then it shouldnt matter so much. I might understand this better when i understand what E is
Exactly, that's why those little bitty MOSFETs can pass such huge currents...because there's no resistance across them.

Fudge factor? I couldn't tell you. I suppose as much fudge factor as your wallet and the circuit board can support...