A4988 Stepper motor controler

The perfect stepper motor controller for 3D printers

Since January 21, 2015, we are distributing the A4988 controller produced by Pololu USA.

This breakout card supports an Allegro A4988 Microstepping driver (DMOS) including over-current protection. It is the step-by-step motor controller that can be found on the control cards of 3D printers (for example: OrdBot Hadron), plotter, etc.

This controller allows you to control bipolar micro-stepping motors with a maximum of 2 Amps per coil (pay attention to heat dissipation conditions!!!).

Here are some key features of this breakout:

• Very simple step and direction control interface.
• 2.54mm spacing breadboard.
  Really great for use with a breadboard and prototyping plate.
• 5 different step resolutions (see our Wiki for configuration):
  • Full step
  • 1/2 step
  • 1/4 of step
  • 1/8 of step
  • 1/16 of step
• Adjustable current control - a potentiometer is used to set the maximum current. this make it possible to use higher voltage on the motor (since the current is limited) and thus makes it possible to reach a higher step rate. Indeed, higher voltage means higher magnetic field which imply a more reactive rotation so an higher speed.
• An intelligent hash control that selects automatically the right way to decrease the current (fast decay or slow decay)
• Protection (stop) in case of over-temperature, over-voltage, overload/ over-current/ short-circuit. Useful in the case where an overloaded motor reach blockage situation (because the current is soaring up, which must cause the protection).

Technical details

Remember to take note of the technical data sheet of the A4988. Indeed, if he is capable of driving a large current, it cannot do it in any condition, you must be attentive to the heat dissipation.

• Size: 15.5mm x 20.8mm
• Minimum operating voltage : 8 V
• Maximum operating voltage : 35 V
• Current per phase (continuous) : 1,2 Amp
• Maximum current per phase :  2.3 Amp
• Control logic
  
  • Minimum voltage : 3 V
  • Maximum voltage : 5.5 V
• Microstep resolution: complete step or micro-stepping 1/2, 1/4, 1/8 and 1/16 of step
• Reverse voltage protection : NO

• Technical data sheet of the A4988 (pdf)