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Drv8825 vref cant go high enough

Hello, I’m using the drv8825 to control my stepper motor, but when setting the vref, I’m not able to get it up to my calculated value (0.85), and the value maxes out at around 0.35V.
Am I doing something wrong?

Hello.

Can you tell me where you got your motor driver? There are a lot of knockoffs of our stepper motor driver carriers out there. Are you sure you have a DRV8825 carrier we made?

Can you post some pictures of your setup, including close-up pictures showing both sides of your board and all of the soldered connections?

By the way, if you are using our driver, keep in mind that a 0.85V VREF value would correspond to a current limit of 1.7A, which is a little higher than what we expect the board to be capable of handling without additional cooling. In our testing, the board could continuously deliver about 1.5A in an open, room temperature environment.

-Patrick

Hi, I don’t have access to my board right now, but for the motor, I’m using the 17hs4401, which on this datasheet (17HS4401 Datasheet PDF - Datasheet4U.com) says it’s rated for 1.7A. As I needed a vendor closer to my location, I got the DRV8825 from here: https://tinyurl.com/35bz8tfe.

Unfortunately, the site you linked to is not for one of our authorized distributors, and the pictures do not look like any of our products, so you probably do not have our carrier (in which case we cannot help you troubleshoot it since it could operate differently from ours). However, if you post clear close-up pictures showing the top and bottom side of your actual board once you get access to it, then I can let you know for sure whether it is our board.

For future reference, here is a link to our list of authorized distributors in Taiwan. If you want to be certain that you are ordering one of our products, I recommend ordering from one of them directly.

- Patrick



these are the pictures of my setup
I can add some more if you need different angles
the red and grey wire coming from vmot and ground go to the power supply*

Thank you for the pictures. Unfortunately, as I suspected, that is not one of our boards, so I suggest you try to contact its manufacturer.

- Patrick