That doesn't sound attractive. Needing an RTC battery to workaround a powering issue.A Pi 5 could also enter the shutdown state due to an under-voltage event.
To ensure it doesn't stay in the shutdown state you could bit an RTC battery and have a script which periodically sets the RTC alarm ensuring that it will wakeup if it does get shutdown
https://www.raspberrypi.com/documentati ... -clock-rtc
It also makes me think immediately of a setting in standard PC BIOS where you can choose/set what to do in case of a power drop. 1 PC defaulted to 'not start but initial standby'. That has caused lots of time-loss and trouble, needed to travel to see what was going on. Also PCs usually don't have easy serial console cable where you can do quick fix / monitoring via CLI what the issue is. So old VGA monitor or so needed.
The Pi3B I mentioned has an RTC module as RPIOS pre-Bookworm messed up time (absolute UTC time) at boot. With RTC active in config.txt, no issue anymore. But I switched to Debian Testing before Bookworm release and that does not support overlays also not that RTC model. But handling of UTC time (or CET CEST whatever) is working fine. So bought RTC for nothing in the end (e-waste in fact).
Other SBCs I have do just hard reset when power is not good enough. So a simple black-white decision. The end-user must simply fix it. On-board DC-DC step-down convertor to creates 5V (and 3V3 and lower of course), so whole issue about '5V 5A' is no issue. It is just some 9V to 20V or so is needed, even when huge ripple from 50/60Hz main grid is there.
Statistics: Posted by redvli — Tue Jun 10, 2025 9:26 am