Optical end stop PNP

  • I have optical endstops that I want to use in my machine for X and Y.
    My board is duet2wifi

    They are PNP type, and are sourcing 5V when triggered. (Omron EE-SX670R - PNP type)
    As far as I know, the duet works with NPN/sinking type switches. Is there a way to make my PNP switches work?

    Random side question, what is the difference between open-collector and line driver?

  • administrators

    As you suggest, NPN types would be more suitable. This PNP switches might work if you connect a load resistor of about 330 ohms between output and ground. If that doesn't work, then a higher value load resistor (e.g. 10K) followed by a 2N7000 mosfet would work.

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