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ESP32 Dual A4988 Stepper Driver Board #

This board integrates an ESP32 (ESP32-D0WD-V3, 16 MB flash) with two onboard A4988 stepper motor drivers, providing a compact and reliable solution for motion control applications.

It is designed for users who want direct ESP32 control of stepper motors without external driver modules, messy wiring, or power-handling compromises.

Key Features #

• ESP32 dual-core MCU (240 MHz, Wi-Fi + Bluetooth)
• 16 MB onboard flash
• Two A4988 stepper drivers (independent Motor 1 & Motor 2)
• Motor supply: 8–35 V (VMOT)
• Logic supply: 3.3 V (fixed)
• Max coil current: up to 2.0 A per motor (with heatsink)
• Recommended continuous current: ≤ 1.2 A
• ROSC tied to GND (internal fixed off-time, stable operation)
• Microstepping selection via DIP switches
  • Full, 1/2, 1/4, 1/8, 1/16 step
  • MS1–MS3 selectable via onboard switches (3.3 V / GND)
• Separate power domains for logic and motors
• USB-C programming port
• External power OR-ing via diode (USB + external supply safe to connect together)

Power Architecture #

• Motors are powered from an external 8–35 V supply
• ESP32 logic runs from regulated 3.3 V
• USB power is diode-isolated from the main board supply
• When USB and external supply are connected together, the higher voltage source automatically powers the board
• No back-feeding into USB

Programming & Safety Notes #

• Disconnect motors during firmware upload
  • USB power may not be sufficient to drive motors and the full board
• Do not hot-plug motors while powered
• Set VREF appropriately before connecting motors

These precautions ensure long driver life and stable operation.

Ideal Applications #

Custom firmware motion control using Wi-Fi or Bluetooth

CNC controllers

Robotics

Linear actuators

Automation projects

Network-connected motion systems