Overview
This product is a carrier board or breakout board for Allegro’s A4988 DMOS Microstepping Driver with Translator and Overcurrent Protection; we therefore recommend careful reading of the A4988 datasheet (1MB pdf) before using this product. This stepper motor driver lets you control one bipolar stepper motor at up to 2 A output current per coil (see the Power Dissipation Considerations section below for more information). Here are some of the driver’s key 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
- 4-layer, 2 oz copper PCB for improved heat dissipation
- Exposed solderable ground pad below the driver IC on the bottom of the PCB
This product ships with all surface-mount components—including the A4988 driver IC—installed as shown in the product picture.
This product ships individually packaged with 0.1? male header pins included but not soldered in; we also carry a version with male header pins already soldered in. For customers interested in higher volumes at lower unit costs, we offer a bulk-packaged version without header pins and a bulk-packaged version with header pins installed.
The Black Edition has the same component layout and pinout as our A4988 stepper motor driver carrier, so it can be used as a higher-performance drop-in replacement in applications designed for our original drivers. The Black Edition achieves its higher performance through its four-layer printed circuit board (PCB), which better draws heat out of the A4988 driver—while our original carrier can deliver up to approximately 1 A per phase in full-step mode without a heat sink or air flow, the Black Edition can deliver up to approximately 1.2 A under the same conditions.
Note that we carry several other stepper motor drivers that can be used as alternatives for this module (and drop-in replacements in many applications):
- The DRV8825 carrier can deliver more current over a wider voltage range and offers a few additional features.
- The DRV8834 carrier works with motor supply voltages as low as 2.5 V, making it suitable for low-voltage applications.
- The DRV8880 carrier offers dynamically scalable current limiting and “AutoTune”, which automatically selects the decay mode each PWM cycle for optimal current regulation performance based on factors like the motor winding resistance and inductance and the motor’s dynamic speed and load.
We also sell a larger version of the A4988 carrier that has reverse power protection on the main power input and built-in 5 V and 3.3 V voltage regulators that eliminate the need for separate logic and motor supplies.
Some unipolar stepper motors (e.g. those with six or eight leads) can be controlled by this driver as bipolar stepper motors. For more information, please see the frequently asked questions. Unipolar motors with five leads cannot be used with this driver.
Included hardware
The A4988 stepper motor driver carrier comes with one 1×16-pin breakaway 0.1"" male header. The headers can be soldered in for use with solderless breadboards or 0.1"" female connectors. You can also solder your motor leads and other connections directly to the board. (A version of this board with headers already installed is also available.)
