Can the input volt of I/O be higher than MCU VDD?

[Yi-Wei]

I want to design NRF52832 with 2.5 VDD and connect to an UART IC (CP2012),

unfortunately, "CP2012" just work in minimal 3.0V.

So, here is the question,

When NRF52832 work with 2.5V, It is can accept 3.0 or 3.3V I/O input?

[Sigurd]

Hi,

Yi-Wei said:

When NRF52832 work with 2.5V, It is can accept 3.0 or 3.3V I/O input?

No, as shown here, the max I/O pin voltage is VDD + 0.3 V. When you have powered the nRF52832 using 2.5V, then the maximum pin voltage is 2.8 V.

The easiest solution is just to run the nRF52832 at 3.0V, but if that is not an option, then might be able to find suitable a bi-directional level shifter that solves this.