A4988 Stepper Motor Driver half output voltage?


Using a A4988 Stepper Motor Driver Carrier https://www.pololu.com/product/1182

I am using multiple motor drivers, I have wired up about 25 so far, but I have a few that are sending half the voltage it should be.

Using 12V motor power supply. Output of 1A, 1B, 2A and 2B are reading 6v.

any ideas?

What are the motor characteristics (voltage rating, current rating, winding resistance)?
What is the current rating of the power supply?
What current limit setting do you use on the A4988?
How are you measuring the “half output” voltage?

Hi Jim,

Thanks for your reply, but I actually fixed it, a few of the outputs were shorted together.

Thanks for your help.