STM32L071 is VDDIO2 needed if not using PA11 and PA12 ?

[YohannDrc2]

Hi everyone,

We are currently designing a board which integrate a STM32L071Ux  with UFQFPN32 pinout.
In the pin description of this package, it is indicated that pin VDDIO2 supply PA11 and PA12.
As we are not using some pins including PA11 and PA12, we are thincking about not connected VDDIO2 to power supply.

I didn't find more info about the goal of the VDDIO2 pin, can it has side effects on this microcontroller ?
And if not using PA11 and PA12 is it recommended to connect or disconnect VDDIO2 pin ?

Thank you for your time.
Yohann

[SofLit · Accepted solution]

Hello @YohannDrc2 and welcome to the community,

To ensure a reliable operation of STM32L071Ux microcontroller, it is advisable to connect the VDDIO2 pin to a power supply, even if you are not using the associated I/O pins PA11 and PA12. This will help avoid any potential issues and ensures that all parts of the microcontroller are properly powered and can help avoid a potential side effects

[YohannDrc2]

Hi,

Thank you for the quick and clear answer.

We also have older an design which integrates an STM32L07xxx without having the VDDIO2 pin connected.
Is there known issues for design integrating STM32L07xxx without having the VDDIO2 pin connected. ?

[SofLit]

As I said we don't guarantee the behavior of the product if VDDIO2 is not connected. If it was working in an older design that doesn't mean it is a safe one. So we don't guarantee a good behavior of the product.

[YohannDrc2]

Well noted.
Thank you for your time.

Have a nice day
Yohann