HiLetgo PCA9685 16-Channel PWM Servo Driver
16 servo channels over two I²C wires, with a dedicated servo power terminal.
Best for: Any arm with 3+ servos
by ACEIRMC
★ Best for: Stepper SCARA, delta & 3-axis arms
Plug-in stepper control for an Arduino UNO: one shield, four A4988 drivers, four heatsinks.
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A CNC shield is the quickest way to turn an UNO-format Arduino into a controller for a stepper-driven arm. It sits directly on the board, gives each axis a socket for a driver module with its own step, direction and microstepping jumpers, and brings out endstop inputs for homing. This kit includes four A4988 drivers and heatsinks, enough for a SCARA arm (shoulder, elbow, Z) with one axis spare, or a three-motor delta. Set each driver's current limit before powering the motors, and feed the shield's motor input from a separate supply sized for your steppers. The UNO board itself is not included.
| Board | CNC Shield V3 (UNO form factor) |
|---|---|
| Drivers | 4× A4988 |
| Includes | 4× heatsinks |
| Not included | Arduino UNO |
ACEIRMC CNC Shield V3 with 4× A4988 Stepper Drivers
See the current price, stock and reviews on Amazon.
Build a stepper motor robot arm with NEMA 17 motors: torque, reduction, drivers, microstepping, AccelStepper code, homing with endstops, and when to use servos.
The conceptsWhat makes a SCARA arm fast and precise for pick-and-place tasks, how its 4-DOF geometry works, and the best paths for building or buying a DIY SCARA robot arm.
The conceptsHow a delta robot arm works — parallel manipulator geometry, inverse kinematics, why delta robots are faster than serial arms, and the best DIY build paths.
Parts & hardwareHow linear actuators work in robotic arms, the main types (electric, pneumatic, hydraulic), when to use a linear actuator instead of a servo, and budget DIY options.
16 servo channels over two I²C wires, with a dedicated servo power terminal.
Best for: Any arm with 3+ servos
PCA9685 driver from a known education brand — works with Arduino and Raspberry Pi.
Best for: Raspberry Pi arms
Two PCA9685 boards — keep a spare or chain them for 32 channels.
Best for: Large or dual-arm builds
ACEIRMC CNC Shield V3 with 4× A4988 Stepper Drivers
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