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Backwards drivers?

Aisling Lightworks
 

So, I just finished a lot of buttoning up on my mount and I think I stuck my drivers in backwards and tried to power it up. Now it won't boot up. Can having the drivers in backwards fry the stm32? I'm assuming it can but I just wondered if anyone knows for sure.

Aisling Lightworks
 

Also, for extra credit, is it safe to assume the drivers are also fried?

Khalid Baheyeldin
 

The China made drivers have a sort of standard to avoid this: pins are black on one side and coloured on the other (e.g. blue for FYSETC LV8729, green for MKS LV8729, ...etc.)

The black side is always the output of the motors, and the colour side is the microcontroller side.

If you put it backwards, then probably the thing that would cause problems is VMOT going to the DIR pin, and GND to the STEP pin.

I did flip the drivers once, but there was no ill effect (on the drivers, or the microcontroller).
Not sure if I was just lucky or what.

Dave Schwartz
 

I would think at a minimum that the driver's would be damaged. When rotated 180 degrees, the 12/24V coming in on Vmot would be applied to DIR and the driver's Vmot and logic GND would have been connected to STM32 pins not designed for power. That could have caused a current flow in unecpected paths and exceeded ratings in both devices.


On January 12, 2020 5:53:05 PM EST, Aisling Lightworks <stercust@...> wrote:
Also, for extra credit, is it safe to assume the drivers are also fried?

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Sent from my Android device with K-9 Mail. Please excuse my brevity.

Aisling Lightworks
 

Thanks, guys, yeah I was pretty sure I sent 24v in all kinds of inappropriate places by doing that. Already have more drivers and bluepills ordered. Just when I thought I was done with it 

Dave Schwartz
 

That's why they are in sockets. Highly likely the PCB is okay.


On January 12, 2020 6:21:45 PM EST, Aisling Lightworks <stercust@...> wrote:
Thanks, guys, yeah I was pretty sure I sent 24v in all kinds of inappropriate places by doing that. Already have more drivers and bluepills ordered. Just when I thought I was done with it 

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Aisling Lightworks
 

Nah, I can't get it to power up. It's got 5V on the power pin but the led light isn't on the bluepill. Also, when the bluepill is plugged in, the wifi won't work. But the wifi turns on and I can connect to it if I power up the board without the bluepill in it. So it's definitely whacked.