This product is a a4988 DMOS and Allegro micro step drive and over-current protection breakthrough in translation. The stepper motor driver, the product can be in full, half, 1/4, 1/8 and 1/16 stepper mode operation of bipolar stepper motor, up to 35 V + 2 A output drive capability Translator's key to A4988's easy to implement. A step input of a micro step motor driver only needs to input a pulse. There is no sequence tables, high-frequency control lines, or complex interfaces. The A4988 interface is an ideal fit for application in a complex microprocessor that is not available or too heavy. Simple steps and direction control interface; The five step: different resolutions full step, half step, step by step, eighth step, sixteenth step; Adjustable current control allows you to set the maximum output current with a potentiometer, which allows you to use the rated voltage of the stepper motor in order to achieve a higher rate of step voltage; Intelligent chopper control, automatic selection of the correct current decay mode (fast decay or slow decay); Over temperature shutdown, under voltage lockout, and cross current protection