Allegro’s A4988 microstepping bipolar stepper motor driver features:
-Adjustable current limiting
-Over-current and over-temperature protection
-Five different microstep resolutions (down to 1/16-step).
-Operates from 8 V to 35 V and can deliver up to approximately 1 A per phase without a heat sink or forced air flow (it is rated for 2 A per coil with sufficient additional cooling).
This board ships with 0.1″ male header pins included but not soldered in.
The sense resiters on these boards are 0.1 Ohm so the formula for setting the Vref is a bit different from that of the pololu drivers.
Ipeak = Vref/(8*Rs)
where Rs - is the sense resistor value.
Ipeak - Is the maximum current you want to use per coil. I usually make my IPeak 70% of the maximum of the stepper.
thus Vref = IPeak/1.25. For 1.19A it is therefore 0.925V