Stepper Motor Driver - Hardware details
Pinout
Click here for a high reoslution image of the pinout.
Pin details
| Pin Marking | Pin Name | Description |
|---|---|---|
| IN1 | Stepper Coil A1 | First terminal of Coil A in the stepper motor. |
| IN2 | Stepper Coil A2 | Second terminal of Coil A in the stepper motor. |
| IN3 | Stepper Coil B1 | First terminal of Coil B in the stepper motor. |
| IN4 | Stepper Coil B2 | Second terminal of Coil B in the stepper motor. |
| GND | Signal Ground (Microcontroller) | Ground reference for the control signals from the microcontroller. |
| VCC | Motor Supply Voltage (+) | Positive DC voltage input for the stepper motor power supply. |
| GND | Motor Ground (-) | Ground connection for the stepper motor power supply. |
As for the actual stepper motor connection, this is the pinout of the connector, in relation to the input pins:
Jumper Details
This board contains hardware jumpers, see below for their locations and functions:
| Jumper | Default State | Function |
|---|---|---|
| JP1 | NC (Normally closed) | Enables the power indicator LED, which indicates when power is supplied to the stepper motor. |
| JP2 | NO (Normally open) | When shorted, it enables the output LEDs that pulse for each pin. |
Dimensions
- Board Dimensions: 38 × 22 mm (1.5 × 0.9 inch)
- Header Pin Holes: 1.5 mm
- Screw Holes: Designed for M3 screws (3.2 mm diameter)
- Soldered boards are LEGO compatible! 🧱
Motor
The version of the product with the stepper motor ships with the 28BYJ-48 5V DC stepper motor. It's cable fits the connector on our basic stepper board and can just be plugged in. This motor has 2048 steps per one revolution. See below for a pinout in relation to the internal coils:
Hardware repository
Schematics, KiCad files, Gerber files and more can be found in the GitHub repository:
Basic stepper driver Hardware design
GitHub hardware repository for this product
The hardware repository contains everything you need to understand, modify, or manufacture the board. The different output folders are versioned. You can check which board version you have specifically by finding the version mark on the PCB.
Below is an overview of the available files.
CAD files
We use KiCad, an open-source PCB design tool. You can open and edit the .kicad_pro project file, which includes both the schematic and PCB layout.
The PANEL files are used internally for production.
Schematic
The OUTPUTS folder contains the schematic in .pdf format, exported from KiCad.
BOM (Bill of Materials)
The bill of materials (BOM) is provided in two formats:
- A standard
.csvtable, listing all components, part numbers, and values. - An interactive BOM (
.html) that visually highlights each component on the PCB, making it easy to locate and reference parts.
3D files
A 3D model of the PCB is available in .step format, allowing you to inspect the board design in CAD software.
Gerber files
Gerber files are essential for PCB manufacturing, as they contain precise instructions for each layer of the board. The repository includes standard Gerber outputs in a .zip file, such as:
- Copper layers (
.Cu.gbr) – Defines the traces and pads on the board. - Solder mask layers (
.Mask.gbr) – Specifies the protective solder mask. - Silkscreen layers (
.Silkscreen.gbr) – Contains text and component markings. - Paste layers (
.Paste.gbr) – Used for stencil fabrication in SMD assembly. - Drill files (
.drl) – Provides drilling coordinates for vias and holes. - Board outline (
.Edge_Cuts.gbr) – Defines the shape of the PCB. - Gerber job file (
.gbrjob) – Describes the set of Gerber files used for production.
These files are ready for fabrication and can be used in PCB manufacturing.
Compliance
The Compliance section includes important regulatory and safety documentation for this product. These files ensure compliance with relevant industry standards and legal requirements.
- CE – Certification document confirming compliance with EU safety, health, and environmental requirements.
- UKCA – UKCA (UK Conformity Assessed) certification for the UK market.
- Safety Instructions – Safety guidelines and precautions in English and in German.
- Info.txt – Contains product details such as SKU, country of origin, HS tariff code, and barcode.