im working with a 12v automotive circuit what im tryin to do is change the signal voltage (which draws no current) from a 2.8V-7.8V system to a 0V-5V signal to be read by a programer and add 2.8V to the signal leaving the programer to change the output back to a 2.8V-7.8V signal.
somthing like:
somthing like: