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DRV8825 0.025V at Vref


#1

Hello,
I am using DRV8825 to drive my Biploar Stepper motor. Name of my stepper motor is KS42STH34-1504A, which according to my internet search has 1.5A current/phase . I have been trying to set the current limit, but so far i have not succeeded in doing so.
I am connecting 12 V, 1 Amp PSU to Vmot, and i am connecting Arduino Uno 5V to RESET and Sleep pin. As long as i turn on the only12 V PSU, DRV8825 doesnt heat up and i get 0V at potentiometer. As soon as i turn on my arduino and provide 5V to Reset and Sleep pins, DRV8825 get very hot and i read 0.025v at the potentiometer and 12v at the hole near M2 pin.
I dont know what is wrong with the connections. I have made connections similar to the one made in the website. I have not connected the motor yet.
P.S:
I have used

  1. white wire for ground connections.
    2.red wire for Vmot
    3.gray and maroon wire for reset and sleep pin which is connected to a to +5v of arduino uno through bread board.

Please help.
Thank you in anticipation.
Karthik


#2

I have also connected to 100uF capacitor between vmot and gnd. I have tried directly connecting the capacitor the vmot pin and gnd pin. Their is no change.


#3

Hello,

From your picture, it does not look like you have one of our DRV8825 driver carriers (our DRV8825 boards have our logo and other details on the bottom silkscreen). Some knock-off versions of the DRV8825 carriers have known issues with the VREF via, as discussed in this RepRap blog post. If you got those DRV8825 boards somewhere else, I suggest contacting the manufacturer to see what they recommend.

-Tony