So I am trying to read some of the sensors on my car i.e. take their voltage output signal and have the Arduino interpret it. I am using an Arduino pro mini @ 5v.
The sensor gives an output between 0-12v for the ECU, I need to get a 0-5v signal from this to go an analog input on the Arduino, without interrupting or altering the voltage that the ECU sees.
Could I use an op amp (with the 12v signal from the sensor going to the non-inverting input) in unity gain arrangement, then just use a voltage divider on the output signal of the op amp to step the voltage down to 5v for the Arduino. I will also filter the signal with a 1Hz RC filter. I am assuming this would work as the op amp has infinite input impedance.
Thanks