Sorry for the delay in etting back to you!
First of all - you are treading on slightly unstable ground using a non-inverting configuration.. Doesn't mean it's not advisable, just requires some tinkering to get things right. Not such a big deal wih a single input however.
If you want to see 1v become 5v then you are looking at a gain of 5. Gain is "basically" the ratio of the output to the input whether it's volts, current, watts, etc...
I'm assuming you read "Op Amps for Everyone"
but I'll go ahead and give you the spoiler. Don't read further unless you give up haha!
In a nutshell, the gain of a
non-inverting op amp is set by the voltage divider network applied to the inverting (-) input of the op amp... plus one (don't forget that). so... lets see a picture and go from there.
R1 and R2 create a voltage divider network applied to the (-) input of the op amp. So if R1 is 2K and R2 is 500 then the ratio is 4 (2000/500). Add 1 to it and that equals 5. Thats what you want --- a gain of 5. It's simple but yet it's complex. I always hated analog circuit design
Now, the Rs on the input? That our tweaking resistor. It doesn't affect the gain of the circuit but it helps "clear the mud' I guess you could say. Make that resistor somewhat near the value of the parallel resistance of R1 and R2. Here's another hint... it's gonna be close to the ratio of R1 and R2 usually.
Hope that helps!
Rob
***edited because my math was taking a nose dive***
***second edit****
Here's the math:
Vout/Vin = R2/R1 +1
You are right that you can't get the numbers with only a simple equation and two numbers. Pick a pseudo-random value for R2 and start extrapolating and matheme-cating
Here is how my simple brain works: Say I want to take a 0v5 signal and make it a 2v5 signal? I divide 2.5/0.5 and get 5. That's my gain. So how do I get it? I subtract one from it and design the circuit around a gain of 4 (if it's a non-inverting amp).
