https://devzone.nordicsemi.com/f/nordic-q-a/22551/nrf52-and-9v-batteryHello, I am trying to design a power supply circuit for my project based around the nRF52 and various sensors. I need to use the 5V pin so I will need a bigger battery than the CR2032. I was thinking about connecting a 9V battery directly to theen-USTelligent Community 13Mon, 05 Jun 2017 21:08:42 GMThttps://devzone.nordicsemi.com/thread/88731?ContentTypeID=1Mon, 05 Jun 2017 21:08:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:34026d79-0e91-4dce-be32-f01dff9681a3Levi<p>Thanks for the help. Looks like I&#39;ll have to use an external voltage regulator!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/88733?ContentTypeID=1Mon, 05 Jun 2017 21:07:24 GMT137ad170-7792-4731-bb38-c0d22fbe4515:bfa3fbd3-317c-4f09-8b17-e6eaefa86f77Levi<p>Looks like I&#39;ll have to use an external voltage regulator to go from 9V to 5V. Thank you!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/88730?ContentTypeID=1Mon, 05 Jun 2017 20:25:04 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2b4652fe-9a8e-4682-a08e-624ffe5f35a2butch<p>Do you mean the NRF52DK dev board? And the 5V pin that is to an Arduino shield? I don&#39;t know of any documentation about the voltage regulator, but the schematic is available. As an alternative, can you use 3 1.5V AAA and connect to P21, external power? Then you wouldn&#39;t need to worry as much, since I think the 4.8V would be close to USB voltage level. But check the schematic, for where P21 supplies power. Maybe there is better documentation for P21 than for the USB port.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/88732?ContentTypeID=1Mon, 05 Jun 2017 20:16:56 GMT137ad170-7792-4731-bb38-c0d22fbe4515:3ceef66d-9be1-467a-9875-d1c3589e13d0RK<p>Not even close. The spec sheet for the nRF52840 shows max input voltage on the USB pins is 5.5v.</p><div style="clear:both;"></div>