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nRF52832_QFAA problem with NFC pins

Hello!

We designed and manufactured board with nRF52832_QFAA. The NFC pins was configured as IO and connected to sensors. The problem is that we see that those pins get 3.3V with power-up of Nordic. We tried to make different configurations for those pins but because that there are no delay between 3.3V rise and those pins rise - we can only power down them when SW at Nordic do this. This situation is harmful to our sensor and make them damage. We removed the sensor and still saw 3.3V at those pins. We removed the nRF from the board as we thought that maybe the board make this and saw that pins now get 0V at power-up of 3.3V of the system which can show us that 3.3V to those pins come from the nRF.

We tested evaluation board and there are was no this issue on NFC pins.

By the way - all other pins at our board behave as needed.

We also reviewed the Errata and didn't find issue about this.

Can someone explain why it happened? Maybe the interaction between the nRF52832 and the board cause this? But how? And how we can to solve this problem at current design. For now we cut this IO from the sensors so it no make damage to them. We was lucky that this IO is no must for us to communication between the sensors and nRF - it just interrupt out from nRF to sensors.

Thank you

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