Seeking "dummy proof" alternative to A4988

I’m a total newb trying a small DIY robotics project involving an Arduino Uno, a SOYO stepper motor, a wooden turntable, and some sort of stepper motor driver. It has been decades since I dealt with volts, amps, or breadboards; I held a soldering iron in my hand for the first time just a few days ago.

In the last week, I’ve trashed three "A4988 Stepper Motor Driver Carrier"s in a row. They work at first and then invariably I make some sort of mistake and the board is broken. On the first board, the screw head for the potentiometer broke off and the motors leads stopped working/showing voltage. In the second, while trying to measure amperage going into the motor on a multimeter (trying to debug a knocking noise in the motor; suspected overamperage), there was a spark and then no voltage on the motor leads. In the most recent event, I’m not even sure what happened, but while initially working, now when the wire from the Arduino plugs in to the “STEP” pin it fails to exceed a voltage of 1.0 when HIGH (reads the correct 5.0 when unplugged from the A4988), and there’s no voltage on the motor leads, leading me to believe I’ve shorted something somewhere.

I like the A4988 at this point because I understand how it works and mostly how to use it, it works well when it does work, it’s relatively cheap, and it has the microstepping options I need for my project (hoping to make use of the 1/8 and 1/16 stepping). I just hate that I keep messing them up, and then I have to wait forever for a new one in the mail (off topic: how does nobody in San Francisco carry this in store?).

What is an equivalent board that’s super hardy against rookie mistakes?

We’ve all made those mistakes, and sometimes with much, much more expensive equipment. You will get better at avoiding them!

You should not try to read the motor current directly. There is a clearly documented procedure for making that measurement indirectly. Direct measurements won’t give useful readings and it is very easy to destroy the drivers by disconnecting motor leads while everything is powered up. There is no way to protect the circuit from high voltage inductive spikes.

[quote]the wire from the Arduino plugs in to the “STEP” pin it fails to exceed a voltage of 1.0 when HIGH (reads the correct 5.0 when unplugged from the A4988)[/quote]This is might be due to the failure to declare the pin as output. Writing a “1” or HIGH to an input pin turns on the pullup resistor, which can lead to such an effect.


I am sorry that you have had so much bad luck with your drivers. As Jim said, we have all broken our fair share of boards with simple mistakes, but it does get easier to avoid. Unfortunately, we do not have a more plug-and-play version of our A4988 carrier, and I don’t have any recommendation for where you would find one. However, we do have a video that goes through the proper steps for setting the current limit on our stepper motor drivers and also covers a few tricks and pitfalls, which might be helpful to you.


Jim, Claire,

Thank you to you both. Claire, your video is particularly well done and useful.

Given all of this, I’ll just chalk it up to learning, and buy a few more I guess.