https://devzone.nordicsemi.com/f/nordic-q-a/35135/totally-isolate-the-nrf52840-on-the-preview-dkHi! I would like to completely isolate the nRF52840 on the Preview-DK (2017.32) on hardware level. Scenario I would like to power the nRF IC with the external supply pins without having to attach a USB cable. When I apply power to the external supplyen-USTelligent Community 13Wed, 06 Jun 2018 11:48:08 GMThttps://devzone.nordicsemi.com/thread/134918?ContentTypeID=1Wed, 06 Jun 2018 11:48:08 GMT137ad170-7792-4731-bb38-c0d22fbe4515:eddc3053-359b-4513-94c2-a25c2f1d2442Stian R&#248;ed Hafskjold<p>No I&#39;m sorry, that&#39;s not possible.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/134903?ContentTypeID=1Wed, 06 Jun 2018 11:25:47 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2a362eac-fec9-4065-b4f4-9af8a278cd93Alpha<p>Hi Stian, thank you for your answer. You are totally correct and that is the issue I am currently having.</p> <p>Is there a possibility to completely isolate the nRF from those components?</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/134900?ContentTypeID=1Wed, 06 Jun 2018 11:22:13 GMT137ad170-7792-4731-bb38-c0d22fbe4515:6f39b374-fbd0-402c-857c-119fc97781cbStian R&#248;ed Hafskjold<p>If you choose to use the &#39;VEXT-&gt;nRF&#39; switch you have to connect the USB cable in order to power all the other components on the board. The &#39;nRF only&#39; switch isolates the nRF chip by using a series of IC switches, but if the USB is not powered these ICs are floating and the nRF not properly isolated.</p><div style="clear:both;"></div>