The A3977 stepper driver is done and working : ) Last thing I want to check on it is the current waveform and see if the stepper can handle the full 2.5A with a little help from a heatsink and fan. There's a distribution board I made too that goes nicely with these, pics below. These would be great for people with smaller cnc's or 3D printers or any motion control requiring nema 17 and below...however you can use larger steppers you just won't get the full power the larger steppers are capable of with these tiny drivers. I have 3 stepper boards left that are available in about 3 days when the rest of the parts come in so you can go here and get them : ) I will definitely be making more if there's interest including the distribution board. The stepper drivers need a name and I was thinking "THE Stepper Driver"...lol what do you think?
Now for specs. It has a max voltage of 35V and can handle 2.5A per phase. However I wouldn't go over 1A without a heatsink and fan. You have a potentiometer to control max current so you don't damage your driver and you have a manual dip switch to control microstepping or you can do it digitally. It can be run in full step, 1/2 step, 1/4 step, and 1/8th step. Everything can also be changed digitally with an arduino as all the A3977 pins are broke out for you to take advantage of.