https://devzone.nordicsemi.com/f/nordic-q-a/84744/reset-voltage-for-nrf52840We have given 1.8V supply voltage for nRF52840-QIAA in our application. The following data is given in datasheet: 1) VDD,POR VDD supply voltage needed during power-on reset. 1.75 V 2) VDD Normal voltage mode operating voltage. 1.7 to 3.6 V Ifen-USTelligent Community 13Tue, 15 Feb 2022 10:03:12 GMThttps://devzone.nordicsemi.com/thread/353044?ContentTypeID=1Tue, 15 Feb 2022 10:03:12 GMT137ad170-7792-4731-bb38-c0d22fbe4515:84ecc7b0-c3aa-4d69-a2d2-20e3aa3a8e67Simonr<p>Hi</p> <p>1. In order to power on, you will need 1.75V. Then the normal operating voltage will be able to go down to 1.7V.</p> <p>2. Then the device will likely brown out if the voltage goes below 1.7V according to the VBOR. (see <a href="https://infocenter.nordicsemi.com/pdf/nRF52840_PS_v1.7.pdf">table in PS 5.3.8.4 Power fail comparator in the PS</a>).</p> <p>Best regards,</p> <p>Simon</p><div style="clear:both;"></div>