On Mon, 9 Mar 2020 14:15:17 -0000 (UTC), Martin Gregorie
 declaimed the following:

>Has anybody tried running a Pi Zero from a single LiPO cell such as you'd
>use in a RC model aircraft or a drone? The voltage varies with charge
>from 4.2 v down to about 3.7 v
>
>I think it should work since the Pi has a regulator that drops the 5v
>supply voltage to 3.3 for internal use, but I don't know what minimum
>voltage the internal regulator needs to work correctly.
>

 USB devices expect 5V... So if you don't have at least 5V provided to
the board, don't expect to use anything connected to a USB host port.

 Also, any boards connecting to the pin header that makes use of the 5V
pins will be unusable.

 And if using the USB client port for providing the power, I suspect you
will need to be within USB specs before the regulator even activates.


--
 Wulfraed                 Dennis Lee Bieber         AF6VN
 wlfraed@ix.netcom.com    http://wlfraed.microdiversity.freeddns.org/

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