That’s the clearest explanation I’ve ever found and finally sunk in. Unfortunately I didn’t save the link to the simplest explanation I could find but it said, in essence, if the non-inverting signal voltage (+) is higher than the inverting signal voltage (-), then the output will be positive. It just seems like the smart way to go for a beginner such as myself.Īlthough I’ve experimented with them before, I had to learn a lot more about comparators before I could get this working. That way the amount of voltage being sensed is low, although the LM339 comparator could handle the 24V signal. The output needs to be a 3.3V signal so I can read it with a Raspberry Pi GPIO pin. Further, I want a very cheap solution and I don’t want to use an MCU. For my current project, I need to sense if current is present on a 24V.
