A4988 Stepper Motor Driver with Small Stepper Motor

Support Motor controllers/drivers and motors
1

Hello,

I would like to drive a Small Stepper Motor (sparkfun.com/products/10551) with the A4988 Stepper (A4988 Stepper Motor Driver Carrier, Black Edition).
I need some help to setup the current limit on the onboard potentiometer.
What is the voltage I should read on the ref pin?
The power supply is 10V and the rated current of the stepper is 400mA.

Thank you for your help.
Renaud

2

See the instructional video on the A4988 driver product page: pololu.com/product/2976/resources

3

Hello.

You can find the appropriate equation to determine what voltage to set the VREF pin to under the current limiting section of the A4988 Stepper Motor Driver Carrier page. Please note that VREF is dependent on the logic voltage (VDD), not the motor supply voltage. So, if you change the voltage at VDD, then the current limit setting will also be changed. However, changing the motor supply voltage will not affect the current limit setting. As Jim mentioned, you might consider watching this video, which shows how to properly set the current limit on our stepper motor driver carriers.

-Zach