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Problem with DRV8825


#1

Hello
I bought couple of DRV8825. The first thing I did is limit the current (1.5A) and I was able to do that. Then I soldered one driver and made the connection and I run recommended code using Arduino Mega. I tested another one on breadboard but it did not work at all.

Power Source: 12V
Stepper motor 4 leads (bipolar)

any advices ?


#2

Hello.

From your diagram, it looks like you are not pulling the nRESET and nSLEEP pins high. Those pins need to be pulled high to enable the driver. If doing that does not fix the issue, could you tell me what Vref voltage you set the driver to and post pictures showing your setup?

Grant


#3

Hi Grant,

Thanks for your reply. That’s right I have to pulled them high (3.3V-5V) from Arduino. Also ENABLE have to be pulled down to have it rotates counter clockwise and clockwise.

what the recommendation on how fast the motor should rotate? I can smell something from the motor (no smoke) and a bit warm. I am controlling the steps and the time(usec) between the steps (200steps per a resolution).


#4

2 posts were split to a new topic: DRV8825 current draw jumping


#5

Stepper motors move as fast as you command them to step. The limit of how fast you can step will depend on many factors, but most of all your stepper motor. I am not sure about the smell, but a stepper motor getting warm is not necessarily bad for it. If you could provide a datasheet or link to the specifications for your stepper motor, I might be able to give you additional advice.

By the way, the nEN pin is pulled down on the DRV8825 chip, so you should not need to connect anything to that pin to get your driver to work.

Grant


#6

Hello Grant,

Here the data sheet for the two motors:

By the way, ENABLE in my case has to pulled externally down otherwise it would not rotate to other direction.


#7

Hello.

If you are using a stepper motor driver for each stepper motor, you should set the current limit according to the current rating of its respective stepper motor. (1.5A for one and 0.6A for the other). If you have the a common ground like you do on your diagram, you should not need to pull down the nEN as it is pulled down internally. If you post pictures of your setup, showing your connections I can take a look and let you know if I see anything suspect.

Grant


#8

Hi Grant,

Here is a pic:


#9

Hello

It looks like your DRV8825 stepper motor driver carrier is not one of ours. That board might be configured differently, so that might account for the difference in the behavior of the nEN pin.

By the way, I forgot to mention this in my last response, but it looks like the datasheet for your 0.6A stepper motor has a pull out torque curve in it. You can use that as a rough estimate of the types of speeds that motor is capable of. If you want more advice about getting stepper motors to step quickly, you might find this forum post interesting.

Grant


#10

Hi Grant,

You are right. Thanks for your help Grant!