nrf52840 with 1.8V GPIO setuphttps://devzone.nordicsemi.com/f/nordic-q-a/76305/nrf52840-with-1-8v-gpio-setupHi Nordic, I am using the Raytac module with the nrf52840 inside, I have set my hardware as mode of Reg0 DC/DC enabled. Which disconnected the VDD and VDDH. Also I have givrn the 3.9-4.2V to the pin VDDH. In my code I setup output voltage to be 1en-USTelligent Community 13Mon, 14 Jun 2021 12:47:24 GMTRE: nrf52840 with 1.8V GPIO setuphttps://devzone.nordicsemi.com/thread/315139?ContentTypeID=1Mon, 14 Jun 2021 12:47:24 GMT137ad170-7792-4731-bb38-c0d22fbe4515:85e6fa85-f789-4739-9507-6310b2dcb671liuluan1984<p>thank you. I have fixed it</p><div style="clear:both;"></div>RE: nrf52840 with 1.8V GPIO setuphttps://devzone.nordicsemi.com/thread/315138?ContentTypeID=1Mon, 14 Jun 2021 12:46:49 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e8cfc7a7-148e-4405-a13c-22ba16211438Simonr<p>Hi</p> <p>My guess is that the regulator has already been set to be in the high voltage mode at an earlier stage. Please try doing a full chip erase (<strong>nrfjprog --eraseall</strong> for example) before flashing the firmware setting the device in 1.8V mode again.&nbsp;</p> <p>Best regards,</p> <p>Simon</p><div style="clear:both;"></div>