DRV8825 Alternate Driver


As I have small CNC machine using the DRV8825 driver carrier right now with a Arduino and a the Protoneer shield (blog.protoneer.co.nz/arduino-cnc-shield/). I’m looking at making a much larger machine now. Unfortunately the motors I’m going to need are around 3A motors.

So I did to a initial test just to see if these drivers would even move the motor. They did, but even with a larger heat sink already on them they got pretty hot. So I’m wondering if I take the cooling the chips even farther ( I happen to have some older PC water cooling parts that are not being used that could be retro fitted) if they would still work well or if I shouldn’t even bother and move on to a different setup. Ideally I want to use the same controls for both my machines.

You shouldn’t bother trying to get 3A from the DRV8825. I don’t know if they are cooled below 25C it might be possible to get 3A from them, but their datasheet spec’s them to 2.5A. Generally that means with perfect cooling (case held at 25C) you can get max 2.5A from them. Any more and the heat might not even have time to get to the edge of the casing. Of course if you get the case below 25C maybe you can. But then you eventually risk things like condensation, etc.

Better off either getting a stepper motor with slightly higher voltage rating (thus lower amperage for same torque), at cost of maybe needing to drive the DRV8825 with a higher voltage for the same max rpm, since the higher voltage motor has a higher inductance. This is for the same package/dimensions/quality of stepper.

Or if you really need 3A there are a couple of toshiba drivers on ebay but I hear bad things about them blowing up easily. They are remarkably cheap, though

The Gecko series of industrial motor drivers are (comparably speaking) not expensive and very reliable: geckodrive.com/geckodrive-st … rives.html

Gecko series is a very nice alternative, but compared to the Toshibas (low quality) or Pololus (high quality but not enough amperage), they’re kinda pricey.

but if you are considering splurging for the geckos, do! It’s probably worth it unless you’re on the tightest budget.

No the Gecko series would put me way over my budget. I only have about a $60 budget per axis (Motor(s) + driver).

The machine it’s self is going to have a 72" x 72" x 6" cutting area. So for rigidity of the gantry I had to go a little crazy which lowered my budget for the electronics.

Your budget is unrealistic for this project.

Look for the Toshiba drivers I’ve mentioned,

and do ample research on what blows them up, and which suppliers make better ones.

They are extremely affordable and some people have figured how to make them work O-K if not perfect. I think if you do your research thats your only option.

Hello There,
Another good driver is the VHN5019, there is a DualMotorShield using this chip, and it is good for 3.0 A