https://devzone.nordicsemi.com/f/nordic-q-a/32014/nrf51822-power-on-resethi, I need to know how to use &quot;power on reset&quot;. From the reference document, I can understand BOR and POFWARN. But the POWER ON RESET, I could not get any idea. 1. POR is controlled by software? 2. need any external circuit to drive it? 3.howen-USTelligent Community 13Tue, 13 Mar 2018 13:24:25 GMThttps://devzone.nordicsemi.com/thread/124174?ContentTypeID=1Tue, 13 Mar 2018 13:24:25 GMT137ad170-7792-4731-bb38-c0d22fbe4515:51a7177c-5b86-40ad-a963-db9758dce75aH&#229;kon Alseth<p>Hi,</p> <p>&nbsp;</p> <p>Power-On-Reset is a hardware feature that ensures that the nRF is kept in RESET state until VDD has reached a valid level. This is 100 % hardware controlled, and cannot be controlled in software.</p> <p>This feature does not require any external hardware.</p> <p>&nbsp;</p> <p>Best regards,</p> <p>Håkon</p><div style="clear:both;"></div>