https://devzone.nordicsemi.com/f/nordic-q-a/1402/nrf51822-resets-when-power-drops-below-2-1vHi When I reduce the operating voltage, the nRF51822 with the heart rate demo running resets whenever the voltage drops below 2.1V and does not recover unless I increase the voltage level and reset the chip. According to the datasheet, operation downen-USTelligent Community 13Mon, 27 Jan 2014 16:03:59 GMThttps://devzone.nordicsemi.com/thread/6290?ContentTypeID=1Mon, 27 Jan 2014 16:03:59 GMT137ad170-7792-4731-bb38-c0d22fbe4515:d9fa171c-b312-4b05-9a5f-737b9ec769b9H&#229;kon Alseth<p>Hi,</p> <p>Are you certain that the voltage does not dip under 1.8V and activate the Brown-out-Detector? If you have high ripple on VDD, it can go below and trigger this behavior.</p> <p>Try scoping the VDD line when this occurs.</p> <p>Best regards Håkon</p><div style="clear:both;"></div>