4988

4988 is most commonly associated with the A4988, a stepper motor driver integrated circuit produced by Allegro MicroSystems. The A4988 is widely used in hobbyist and educational electronics to drive bipolar stepper motors.

The A4988 provides microstepping control for a motor, accepting STEP and DIR inputs to determine movement. It uses chopper current regulation to limit coil current and supports microstepping resolutions from full-step up to 1/16 step. The current limit is adjustable via a reference voltage (Vref) set with a potentiometer on many breakout boards, allowing users to tailor torque and heat generation. Protective features include overcurrent protection, undervoltage lockout, and thermal shutdown.

Hardware and interfacing commonly involve separate motor power (VMOT) and logic power (VDD or 5V). On popular breakout boards, pins typically include STEP, DIR, ENABLE, MS1–MS3 for microstep selection, RESET and SLEEP for control, along with VMOT, GND, and VDD. These boards typically use a sense resistor (Rsense) and can be operated at currents up to about 2 A per coil with adequate heat sinking.

Applications and usage are widespread in DIY CNC machines, 3D printers, laser engravers, and general robotics projects. It is often used with microcontroller platforms such as Arduino and Raspberry Pi via breakout carrier boards from manufacturers like Pololu and others, where “4988” is shorthand for the A4988 driver module.

History and notes: The A4988 was introduced by Allegro MicroSystems as a compact, cost-effective stepper driver solution. Over time, it has become a standard component in low- to mid-power motor control, with various clones and compatible boards circulating in the maker community. See also: A4988, stepper motor, microstepping.