Is it possible to configure GPIO on the STM32U5A9J-DK for 3.3V output?

jcmoreau · ‎2024-01-11

I see this note in the user manual for the STM32U5A9J-DK

Is it possible to enable 3.3V output for the GPIO on the CN9 header by removing SB56 and jumping the 3V3 pin to IOREF, or would this damage the board or not have the effect I intend?

TDK · ‎2024-01-11

Based on the schematic, IOREF isn't connected to anything except pin 3 on CN9 (and VDD through SB56). So that doesn't do anything.

https://www.st.com/resource/en/schematic_pack/mb1829-u5a9njq-b01-schematic.pdf

In order to change the IO voltage of pins, you would need to change VDD to 3.3 V. There is also the VDDIO2 pin but that only controls PGx pins. It can probably be done, but would take some investigating to see if everything else on the board can handle that voltage.

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TDK · ‎2024-01-11

Based on the schematic, IOREF isn't connected to anything except pin 3 on CN9 (and VDD through SB56). So that doesn't do anything.

https://www.st.com/resource/en/schematic_pack/mb1829-u5a9njq-b01-schematic.pdf

In order to change the IO voltage of pins, you would need to change VDD to 3.3 V. There is also the VDDIO2 pin but that only controls PGx pins. It can probably be done, but would take some investigating to see if everything else on the board can handle that voltage.

If you feel a post has answered your question, please click "Accept as Solution".