Ground loop when using more than one A4988 Carrier andconnectiing both Grounds

if I understand correctly both GND pins on the Carrier Board are connected through the A4988.
If so does this not automatically create a ground loop when using more than one driver board and connecting both GNDs?

Your question isn’t very clear, post a wiring diagram of your proposed setup.

A ground loop would be a problem if large currents flow along the ground leads, creating a significant voltage drop at the point where signal pins are grounded. That should not be the case with proper A4988 wiring.

If you anticipate significant ground currents, a “star ground” with a single, common connection point is best.

Thanks for taking the time to answer :slight_smile:

This is a Driver board for an EggBot. 5V will be supplied by USB.
As you can see Arduino GND is connected to both Drivers as is the PSU GND.
As I understand A4988 connects these grounds which connects Arduino GND and and PSU GND at two points.

I am unsure if what you said applies. There are high currents flowing through the PSU GND. And the signal pins are grounded though the arduino at the A4988.

Would this design be considered better?

Yes. That would be a “star ground” if the wires to all board GND connections meet at the power jack. Use suitably sized wires to the motor drivers to avoid significant voltage drops along the wire.

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