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    Pull downs for heaters?

    Hardware wishlist
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    • A Former User
      A Former User last edited by

      While being open to overlooking something very obvious wouldn't pull downs on the heaters gate be a safer design if the mosfet driver fails in strange and wonderfull ways?

      I notice that Fan0 and Fan2 does have pull downs, which I guess makes sense as we'd want Fan1 that is normally the hotend fan to run at power on before the firmware takes control; but would we also not want the opposite for all heaters?

      Just had an interesting experience testing if the pwm pins from the microcontroller was working after removing a failed mosfet driver. stuff got nice and toasty. Running the board with no mosfet driver clearly isn't a normal situation, but I would think similar behavior could be triggered by a faulty driver?

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      • dc42
        dc42 administrators last edited by

        The only times I have seen the mosfet driver chip fail, they failed short circuit. I have never seen a mosfet driver chip fail with an open circuit output.

        Duet WiFi hardware designer and firmware engineer
        Please do not ask me for Duet support via PM or email, use the forum
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