I am quite new to the whole microprocessor idea with some general tinkering knowledge (GCSE Electonics...).
I am trying to get an A4988 driver to work "well" with a Nema 17 stepper motor in 1/16 steps.
I have had one running, but believe I somehow manage to break the driver, so ordered a few more.
The particular driver is here: http://www.ebay.co.uk/itm/190972210407?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
I understand I have to limit the current to the motor somewhat when I want to run off a 3 cell LiPo by using the included on driver potentiometer. I understand that the max current of the driver is lower than that of the stepper.
The board however, was connected directly to the stepper with no "protection" as it were. I assume that is where I went wrong and managed to fry it with ENR (or voltage spike etc.).
Should I use say a 5v UBEC on the 3 cell LiPo and limit the current on the coils to 0.8A instead of the 12.6v-10v 3 cell voltage? Is there a way I can dampen the power supply against spikes or should the UBEC provide enough protection from spikes? Should I use an optoisolator or transitor between arduino and the driver?
Thanks for any help!