1.8V Operation in Normal Mode

[mstanisz]

Hi,

We are planning to run the nRF52840 in CKAA configuration 3 (attached) in Normal Mode.  When we boot, our regulator will provide VDD = VDDH = 1.8V.  Reading through the documentation, it appears that 1.8V is acceptable for operating in Normal Mode.  I've also tested this on the nRF52840 DK, though LED1 is very dim due to the low voltage.  Once the firmware sends a command, the regulator will switch to 3.3V mode so that VDD = VDDH = 3.3V.

Can you confirm operating the nRF52840 in Normal Mode at 1.8V is acceptable?  Will switching the power supply into 3.3V mode cause any issues?

Best,

Matt

[ketiljo]

Yes, this is not a problem. As soon as the device is out of POR (power on reset), you can change the supply voltage up or down between 1.7 v and 3.6 V.