The A4988 stepper motor driver carrier is a breakout board for A4988 microstepping bipolar stepper motor driver.
The driver features adjustable current limiting, overcurrent and overtemperature protection, and five different microstep resolutions (down to 1/16-step). It operates from 8 – 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).
As well as the A4988, this listing also includes a very handy shield for the stepper driver. The shield includes female headers for power, male headers for stepper motor control, a DIP switch for step resolution, 4 pin housing for connection to the stepper motor, and an on-board capacitor. Please see below for a description of the breakout board.

Features:

• Simple step and direction control interface.
• Five different step resolutions: full-step, half-step, quarter-step, eighth-step, and sixteenth-step.
• Adjustable current control lets you set the maximum current output with a potentiometer, which lets you use voltages above your stepper motor’s rated voltage to achieve higher step rates.
• Intelligent chopping control that automatically selects the correct current decay mode (fast decay or slow decay).
• Over-temperature thermal shutdown, under-voltage lockout, and crossover-current protection.
• Short-to-ground and shorted-load protection.