What makes it unique?

There are plenty of boards and solutions out there that can drive a stepper motor. However, what I have yet to see is a solution that is completely self-contained, requiring no external power supply and driving a stepper motor using input controls from an operator.

My aim is for this to be an item in your toolbox, one that can be called upon whenever you need to test a motor - without all the setup cost.

It is inherently low power - giving just enough juice to get a motor going but with enough power to test out some motor features.

How much does it cost to build?

Short answer

Around €50 (or $60) per unit

Longer answer...

A core goal from the outset was to make this as cheap as I possibly could. Totting up my most recent order for 5 PCB's with 3 assembled PCBA's and including the additional through-hole components I hand solder to the PCBA's (to reduce cost) works out to around $50 per PCB as per my last order in March 2025.

Tech specs

  • Firmware: Pico-SDK v2.2.0 running FreeRTOS v11.2.0
  • CPU: Dual-core Arm Cortex-M0+ processor, flexible clock running up to 133 MHz
  • RAM: 264kB on-chip SRAM
  • Flash: 2MB on-board QSPI flash
  • Battery: 18650 Li-Ion, single cell (protected or non)
  • Charge current: 300mA
  • Motor control: ~10.2V at 500mA (default) -> 5.1 Watts
  • Battery life: ~5.5 hours in testing using a 3400mAh 18650 Li-Ion battery