Stepper motor power

Just a quick question. Picking up some stepper motors, but confused at what voltage/current things are running off.
2 x Stepper Motor
2 x EasyDriver

This article says

You need some 12V source to the EasyDriver (the motor in this article is 12V) – This will be powering the stepper – Im using a 12V adapter – similar to the one in the illustration. Just make sure it is rated at least 750ma – A higher rating is better, and just means it wont burn out.

So does that mean if I got this plug which is 12V 1A and powered the Arduino from that I could power a rail with VIN pin and that would safely supply the EasyDrivers? And I could then use the 5V pin to power everything else?

Just don't want to break anything! Thanks :slight_smile:

Actually, is this better as it is regulated, so will actually get a safe 12V 1A at the VIN pin?

To start with it will be much easier if you power your Arduino separately - perhaps from your PC's USB cable.

I have those stepper motors and Pololu A4988 drivers and I run them from a 20v laptop PSU. They will also work with 12v, but higher voltages give better high speed performance. The Easydriver can take up to 30v.

People who know more than me have said that an unregulated power supply is best.

Under NO circumstances draw power for the motors from the Arduino.

Stepper Motor Basics

Ok, I was just trying to combine the project into one single power supply as it currently sends data wirelessly and this would mean I wouldn't need the USB to PC.

So it's a bad idea to draw the required power from the VIN pin of the Arduino?

Any suggestions as to what type of power supply I could use so I only have a single wall plug?

If I had a 12V 1A plug like this unregulated one, cut off the 2.1mm plug, exposed the wires and applied power to a breadboard rail. Would it be sensible to then power the arduino using the VIN pin and then use the same rail to power the easyDrivers?

You can certainly split the output from the power supply so it goes to the Arduino and to the stepper driver. There may be a risk that the motor causes interference to the Arduino.

I don't know enough to say whether it is wise to connect 12v to the VIN pin.


Thanks for the help so far Robin!
I have been looking for a safer option and have come to the conclusion that a breadboard power supply might be better. This for example supplies a rail with either 5V or 3.3V, but I can't seem to find one that still allows me to have a 12V pin.
This way I can separate the motor from the Arduino and not have the Arduino voltage regulator taking the strain. Anybody seen one that allows access to the incoming DC voltage?

I can’t seem to find anything that allows me to have a 12V pin. So if I did use this, would it be safe to just solder a pair of wires directly to the jack connector?

Aaaand I have just realised I have gone full circle and the self soldered 12V wires would have to power the Arduino AND the motors :confused:

Scratch that I could use the 5V pin seens as the breadboard power supply is giving 5V. Although I have also just been told this is not recommended :frowning: