Hey

I want to know how I can use the LF411CN op amp to increase a voltage signal of 40 - 200 mV to a 1 - 5 V signal. The gain of the circuit is 25. I've searched the net and cant find a schematic of this circuit

thanks

 

You don't tell as anything about the input signal frequency? The supply voltage and so on. Also the LM411 in this application will need dual-supply.
As for the circuit diagram simply use non inverting op-amp with the gain equal to 25. You don't need any dc shifting here.

 

A rail-to-rail input, rail-to-rail output, modern opamp could do this without needing a negative supply. If powered on +5V, it could pull within mV of +5V when the input is 200mV.

I would make R1 and R3 10K, and R2=240K.

 

Along with what MikeML said, note that the input offset voltage will be amplified by the gain, so you'll either want a very low input offset voltage, or you'll need to null out the input offset to avoid what could be a large error on the output. Since the application hasn't been mentioned, we have no idea how precisely you need the output to follow the input.