Data Sheet

ManualsBrandsPololu ManualsStepper Motor ControllersA4988 Stepper Motor Driver Carrier

RB-Pol-176

Pololu 8-35V 2A Single Bipolar Stepper Motor Driver A4988

A4988

Stepper Motor Driver Carrier

The A4988 stepper motor driver carrier is a breakout board for Allegro’s easy-to-use A4988

microstepping bipolar stepper motor driver and is a drop-in replacement for the A4983

stepper motor driver carrier. The driver features adjustable current limiting, overcurrent

protection, and five different microstep resolutions. It operates from 8 – 35 V and can deliver

up to 2 A per coil.

Note: This board is a drop-in replacement for the original A4983 stepper motor driver carrier.

The newer A4988 offers overcurrent protection and has an internal 100k pull-down on the

MS1 microstep selection pin, but it is otherwise virtually identical to the A4983.

Summary of content (6 pages)

PAGE 1
RB-Pol-176 Pololu 8-35V 2A Single Bipolar Stepper Motor Driver A4988 A4988 Stepper Motor Driver Carrier The A4988 stepper motor driver carrier is a breakout board for Allegro’s easy-to-use A4988 microstepping bipolar stepper motor driver and is a drop-in replacement for the A4983 stepper motor driver carrier. The driver features adjustable current limiting, overcurrent protection, and five different microstep resolutions. It operates from 8 – 35 V and can deliver up to 2 A per coil.
PAGE 2
Description 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 (380k 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).
PAGE 3
Using the driver Minimal wiring diagram for connecting a microcontroller to an A4988 stepper motor driver carrier (full-step mode). Power connections The driver requires a logic supply voltage (3 – 5.5 V) to be connected across the VDD and GND pins and a motor supply voltage of (8 – 35 V) to be connected across VMOT and GND. These supplies should have appropriate decoupling capacitors close to the board, and they should be capable of delivering the expected currents (peaks up to 4 A for the motor supply).
PAGE 4
Motor connections Four, six, and eight-wire stepper motors can be driven by the A4988 if they are properly connected; a FAQ answer explains the proper wirings in detail. Warning: Connecting or disconnecting a stepper motor while the driver is powered can destroy the driver. (More generally, rewiring anything while it is powered is asking for trouble.) Warning: Connecting or disconnecting a stepper motor while the driver is powered can destroy the driver.
PAGE 5
GND. The chip has three different inputs for controlling its many power states: RST, SLP, and EN. For details about these power states, see the datasheet. Please note that the RST pin is floating; if you are not using the pin, you can connect it to the adjacent SLP pin on the PCB. Current limiting To achieve high step rates, the motor supply is typically much higher than would be permissible without active current limiting.
PAGE 6
Schematic diagram Schematic diagram of the md09b A4988 stepper motor driver carrier.