I was looking for a good solution in order to use a bunch of components and read 0-10V/0-20mA and digital inputs using my Arduino Pro Mini (ATMEGA328P working at 3.3V.)
I find this schematic really interesting, it seems that, using a single op-amp, is able to manage: a digital input OR 0-10V analog input OR 0-20mA analog input (as reported at page 8 of the board user manual):
Now, I need to know two things:
- If I wire 3.3V at BAT54S cathode (red circle in the main photo) and the VLIM of the LM224D, will the circuit work without any issue?
- Can anyone help me to understand how this non inverting op-amp was configured in order to work like that?