Chapter 18.6.1 of nrf52832 data sheet: "A step increase in supply voltage of 300 mV or more, with rise time of 300 ms or less, within the valid supply
range, may result in a system reset."

Question

Chapter "18.6.1 Power-on reset" of the data sheet describes " A step increase in supply voltage of 300 mV or more, with rise time of 300 ms or less, within the valid supply range, may result in a system reset." 
 We are using the nrf52832. During Operation, we switch the power supply from 3.0 to 3.3 Volt within short time. The voltage rises from 2.872 to 3.308 volt and fall down after 250 msec to 2.8 volt (see also diagram below) 
 Is ist possible that the Change of power-supply voltage can cause a reset? Actually we could not observe a reset when changing the voltage.

Einar Thorsrud · Answer

Hi, 
 In practice, the tolerable step increase is higher for higher supply voltages, so you probably need a bit more than 300 mV step increase to trigger a reset in your case. There is also a chip to chip variation, so the fact that it works on the device you tested does not necessarily mean that it will work on all devices. 
 Nevertheless, this will most likely not be an issue, but you run a risk of failures once the devices have been deployed in the field. If you're okay with a few devices resetting once in a while, or losing a packet here and there, then you can proceed with this design. If you're doing anything where safety is important then you should redesign the power supply so that the voltage increase is slower.

Chapter 18.6.1 of nrf52832 data sheet: "A step increase in supply voltage of 300 mV or more, with rise time of 300 ms or less, within the valid supply range, may result in a system reset."