GPIO output voltage on nrf52810

[cory123]

I'm powering an nrf52810 with a 3.3V regulator. I understand the internal LDO powers the system at 1.3 V. Are the GPIO pins and other peripheral devices outputting 3.3V for high? In particular I'm connecting an I2C device to the nrf52810. The I2C device runs at 1.8V but has a 3V tolerant I2C interface. If the nrf52810 outputs 3.3V will this destroy my I2C chip?

[bjorn-spockeli]

The output voltage of the  GPIOs of the nRF52810 will equal to the VDD supplied to the chip, see the GPIO Electrical specification section in the nRF52810 Product Specification. 

So if VDD = 3.3V, then the GPIOs will output 3.3V when set high. I do not recommend operating the I2C chip outside its maximum operating voltage. 

Best regards

Bjørm