First of all, thanks for the suggestions. I've been struggling to get a voltage comparator working in some way or another, but am having troubles with getting it to change output.
I'm using an LM311N, which I tested using various reference voltages in the (+) terminal, and 5.03V at the (-) terminal. I had a voltage divider set up with a trimpot to see where the comparator was actually triggering, and the moment it did, I had 3.9V at the (+), and still 5.03V at (-).
This is definitely not sensitive enough for what I need. In PSpice, the LM311 model triggers at pretty much exactly the level I needed. What's going on here? Is the 311N supposed to behave this way... I thought it was the same as the normal LM311.
Should I just go out and find a better comparator?