STM32 Board with 3V3 Power Supply

Thread Starter


Joined May 18, 2021
i am a newbie regarding microcontroller and i have a question.
I am using a STM32 Nucleo-144 developement board and in the datasheet it says that it can be powered with 5V or 3.3V.
Do i get any disadvantage (beside the ST-Link can not be used) if i power the developement board with 3.3V or
why can i power the board also with 5V? Or does the 5V mean that the developement board can be powered with
an USB port (5V) which then gets regulated to 3.3V?

I am referring to this datasheet (page 20-22) :


Joined Oct 2, 2009
In general most development boards are powered from the USB 5V connection.
On board 3.3V regulators are used to power the 3.3V devices such as the STM32 MCU.