Can the input voltage of GPIO pins with analog functions (e.g. ADC, DAC, and ACMP) be higher than AVDD?

[a_ziliu]

To avoid the influence of internal analog circuit signals, the input voltage of the GPIO pins with analog functions, even no analog function is selected, could not be higher than AVDD. Otherwise, it will cause unpredictable errors.

For example, in the M051 series:
If the Config bit is set to 2.2V Brown-out detection and Brown-out reset, as shown below.

At this time, if P1.0 (with ADC channel 0 function) is set to GPIO, but the input voltage is higher than AVDD, the analog circuit voltage may increase, causing misjudgment of the Brown-out detection and the occurrence of the reset.