This USB-C to DC adapter utilizes the USB Power Delivery protocol that turns your USB-PD charger into a programmable power supply. Voltage regulation is done in the USB-PD capable charger, while this adapter only controls the on/off and negotiates the desired voltage with the charger.

If the charger has PD 3.0 PPS feature, the output voltage can be adjusted in the unit of 20mV within the APDO range. Otherwise, only fixed voltages announced by the charger (PDOs) can be selected.

The STM32G071 MCU controls all the communications and user interactions. Complete hardware design files are in the Schematics folder.

Set an environment variable that points to GNU Arm Embedded Toolchain, for example:

export GCC_PATH=/opt/gcc-arm-none-eabi-8-2019-q3-update/bin/

Then build the firmware with make:

make

After a successful compilation, you may download build/UCDC.bin to the STM32 with ST-Link or any other Link you have.

This project is based on the demo code of STM32G071B-DISCO.