I have an input signal which is about 0,21v at max. I want to use the arduino to read it, right now I have it set to internal reference so it can but not accurate.
My tough was to use a opAmp so i bought a LM1458N. The problem is using it. I guess i want non inverting, but how can i limit it to 0-5v?
The signal comes from a ultrasonic transducer btw.