Sprocket Boards

Sprocket Board Renders

This is a breakout board for the STM32G031. Each board is 15.0x47.0mm.

Each board costs under 2.00 EUR/ea at 100 units.

I documented the design process here:

And streamed most of the original design on YouTube here:

The Board

It has:

  • A 28-pin STM32G031
    • 64MHz Cortex M0+
    • 8KiB RAM
    • 64KiB Flash
  • Two WS2812b-style Smartleds
  • Two User buttons
  • Reverse Protection Diode
  • One Power LED (always on)
  • Two User LEDs
  • 3.3v LDO
  • Four QWIIC connectors
  • Three main connectors:
    • One with 8 GPIOs, all with PWM, six with ADC channels and Power
    • One with I2C, SPI, UART, and Power
    • One with SWD connectors, reset pin, and power

The board is meant to be brick mount compatible, and is the same size as a LEGO 2x6 Plate.

The four mounting pins each electrically connect to:

  • +5V0
  • Ground
  • SDA (3v3)
  • SCL (3v3)

These connectors are intended for use with a testing, programming, or configuration jig.

Compatible Add-On Boards

I don't know if I'll make a lot of accessories, but I'll certainly make some.

Clink board

clink board render

This board is intended to take PWM as inputs (on up to eight channels). The PWM signal is buffered by a TI 74HC244D, and sent through an RC circuit, taken from the Raspberry Pi 3B+ Audio.

I don't expect Hi-Fi audio, but might be useful to make appropriate bleep-bloops.

The board also contains it's own 5V LDO to reduce signal noise.