Nucleo-32-f042 overheat

Hello, im trying to fix some Nucleo-32-F042K6, and all of them have the same problem.
The ST890C chip overheat like crazy (almost burnt my finger), I tried to erase the previous program, arduino say it has no enough memory, i tried to use st link utility, cannot connect, BUT i can upgrade them.
It’s my first time using them, but they were used, i don’t know much about what should i do next.
Thank for the help.


When you open a file manager and check the MSD memory, provided by on-board ST-Link, then you will see the memory has just 32Kb or something like that, I think.
This is usually caused when the target MCU is not properly powered or wired with ST-Link. But in the context of overheat on the chip that seems like you have a short circuit somewhere.

STM32 Nucleo-32 boards (MB1180) - User manual
I do not know how you powered your Nucleo, but you probably need to check the board and Voltage regulators what are responsible for power for MCU.

  • U6 - LD1117S50TR
  • U3 - LD39050PU33R

For verifie your MCU is not dead you can remove a small jumper SB14 and put 3v3 from another source to 3v3v pin. Or remove small jumper JP1 and bring 3v3 on of its pin.

I had same on Nucleo-F303K8, after I ordered and replaced both regulators problem was gone.

BR, Jan