https://devzone.nordicsemi.com/f/nordic-q-a/86671/initialization-timeHi Team, I want to know the time with time resolution milliseconds for initialization time of nrf52840 chips and nrf52840 DK with external supply model? KInd regards, Gaoshengen-USTelligent Community 13Wed, 06 Apr 2022 09:18:00 GMThttps://devzone.nordicsemi.com/thread/362009?ContentTypeID=1Wed, 06 Apr 2022 09:18:00 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2ec542f8-54d8-4ad3-8782-cccce8a77f24H&#229;kon Alseth<p>Hi,</p> <p>&nbsp;</p> <p>The startup time for any nRF device will depend on several factors, like supply rise time:</p> <p><a href="https://infocenter.nordicsemi.com/topic/ps_nrf52840/power.html?cp=4_0_0_4_2_7_2#unique_1752780615">https://infocenter.nordicsemi.com/topic/ps_nrf52840/power.html?cp=4_0_0_4_2_7_2#unique_1752780615</a></p> <p>In addition to what you&#39;re doing in firmware and where you&#39;re measuring. Lets say that you add a test point (for instance setting a GPIO) when you have reached main(), the CPU has already executed several functions before and possibly started external clock sources and waited for them to properly stabilize first.</p> <p>&nbsp;</p> <p>Kind regards,</p> <p>Håkon</p><div style="clear:both;"></div>