A4988 stepper motor driver carrier heating problem

I’m trying to drive stepper motor using Arduino Nano and A4988 stepper motor driver. The problem is - when everything is already installed and i’m powering logic 5V VDD-pin (Vmot is not powered yet) - the driver starts heating so much that seems it is going to burn! (Actually one is already burned) And if the VMOT is powered first - the same thing happens. So, it seems that arduino’s 5V is killing the driver. To check my wiring, I installed A4983 stepper motor driver carrier with voltage regulator instead of A4988 - and all work fine. I also used decoupling 100 uF capacitors both on logig and motor power pins, but their presence doesn’t effect somehow notable. Help please, what i’m doing wrong or is this just manufacturing defect? Thanks.

Hello.

Can you please tell us all the wiring connections you are making to the driver without voltage regulators? Also, a picture of your setup might help us see what is wrong.

- Ryan

Sorry for a pause, i was relocating… “Unfortunately” this new scheme works (with new driver and another motor)… The scheme is the same, but now i’m using unipolar stepper. Previous drivers (that were overheated) are still not working here, they heat more and more, providing no current in motor. Potentiometer is set approximately at the middle position. So, everything is fine with new driver and motor. Well, i’m going to get old motor and try it again (to burn driver and understand!). May be the overheating was caused by potentiometer was set to “very low current” position, and too much current was flowing through driver itself?



Is this a picture of your working setup/motor? The connections look good to me.

Can you tell me more about the motor that damaged your other A4983 chips? Do you have a datasheet for it or the page of where you bought it? Are you sure you had everything connected like you do in the picture?

- Ryan