STM32U5G7VJT6Q GPIO Input issue

[NIVI]

Hi,

I'm using the STM32U5G7VJT6Q microcontroller to read input from a few switches. All switches should show a high state when unpressed (due to the pull-up resistor) and a low state when pressed (grounded).

However, one switch is acting strangely:

• When it's unpressed, it stays in a low (reset) state, but it should be high.
• It only changes to high when another switch is pressed.
• The other switches are working fine.
• The switch is connected in the following order: TVS diode -> Pull-up resistor -> RC filter -> GPIO pin.
• The GPIO pins are set as inputs with internal pull-ups enabled.
• The wiring looks correct, and the pull-up resistor is in place.
• The other switches behave as expected.
• Tried removing the tvs diode and capacitor in rc as well, still the same behavior occurs

Note: No input of the switches are shorted or grounded, the behavior is observed in all the boards we fabricated.

Questions:

1) What is the possible cause for this behavior?

[mbarg.1]

I beleve nobody has a glass ball handy ...

You must include at least an ioc file to give you some useful hint.

By sure, there is some problem in configuration, but listing dozen of possible reasons would not help.

Also include versions of IDE, FW, and any other useful info on yuor project - and somebody will try to help you.