Digi-Key Cart: https://www.digikey.com/short/zbtmwp

OSHPark Project: https://oshpark.com/projects/PmwNw73Z

This is a minimal system of STM32G473CxT6 MCU --- all 48 pins, plus +5V power input, are exposed on a compact breadboard-compatible footprint (800 x 2500 mils). Although it looks like a glorified QFP-to-DIP adapter board, it actually has a few features that greatly improve Quality of Life while not adding too much to cost:

  • Micro-USB connector
    • VBUS can be used to power the board
    • Data lines are connected to MCU
  • Flexible power
    • Feed either VBUS or external 5V to on-board 3.3V LDO
    • TVS + reverse-polarity protection on +5V
    • Alternatively use external 3.3V and forget about 5V
  • Cortex Debug Connector (2x5 keyed shrouded 1.27mm pitch)
  • HSE (high-speed external oscillator)
    • Footprint for 4-pad SMD crystal + load capacitors
    • Alternatively free up the pins for GPIO
  • On-board reset button
  • `BOOT0` handling
    • 47k pull-down + 1k pull-up (through jumper)
    • Since `BOOT0` is multiplexed with `PB8` on this package, this setup avoids accidentally back-driving external circuitry.
  • Power LED (3.3V) and "Blinky" LED (PC13)
  • Silkscreen on both side clearly indicating pinout
  • Headers can be soldered on both sides, although back-side male headers are preferred for breadboard compatibility