I've already asked a specific question, but I'd like to evolve it in a more general question.
In a typical optoisolated IC like this:
Should I or not interconnect control (-) and DC (-) or will I lose my optoisolated considerations?
Since there's a MOSFET N inside this IC schematics, should I take in consideration MOSFET typical use with load on drain side? To avoid MOSFET high side configurations.