3,3v Signal Voltage, and motor drivers need 5v

edited April 2016 in Motor Control
Hi, so this little problem has just come to my attention. And a possible solution has come up in the smoothieboard documentation.


But it mentions something about changing pins to open drain, is this something i have to do anything with in repetier firmware?
Or if it will work at all?


  • I can add that i have a radds 1.5. And im beginning to wonder if this is actually possible, the pins on the radds are called 11,12,21,22 and im not sure if that is the EN,DIR,ST and GND i need
  • Usually that kind of drivers also work on 3.3V. Their Inputs are opto Isolated just take care of polarity.
    Problem would be to go higher than 5V then additional resistors would be necessary in each Signal line.
    I cannot say something to pinnumbers, don´t have Radds
  • edited April 2016
    Yeah, well I had quite the brainfart when I wrote the part about the pinout. Those are easy to find

    I will have to try with correct pinout and see if my driver work with 3.3v it it does it will surely make this easier

    A level shifter will do the job nicely if it doesn't ☺
Sign In or Register to comment.