batteries & hub voltage question

Hi there,

If I power my board from a 5v battery to the USB OTG port, and then
plug a usb cable from the USB Host to a 5v powered USB hub, is there a
danger of too many volts hitting the beagleboard?

I'm clearly no electronics expert and I'm totally paranoid about
blowing the board.

I've been happily running my C4 board for a month now, always powered
via my USB hub, either with mains or with a 'regulated 5v Lithium Ion
battery', which was marketed as an mp3 player backup battery.

I'd prefer to dedicate one of these batteries to the Beagle, and
another to power the hub. In this way I should squeeze more life out
of each.

Is it safe to do this?

Sorry if it's a dumb question



This is not an issue and you can do this if you like.


Or, you can plug the OTG port into a powered HUB and run it from there and not need the battery at all


Thanks man,

Grateful for the reassurance

It's for a robot, so the whole thing needs battery power ...

So far, I've been doing exactly that:
  Beagle-USB-host to hub
  hub back to Beagle-OTG
  battery to hub

but now, i want to do this:
  Beagle-USB-host to hub
  battery1 to hub
  battery2 to Beagle-OTG

So, here is the question. Where are you getting the 5V battery from? Tytpically they are higher voltage than 5V.


It's one of these:

They were on special from Maplins (UK), so I bought a couple.

It works great, but not for very long - it's powering my hub, wireless
dongle, bluetooth dongle and beagle all at once, and I get half an
hour out of it.

I figure if it were only powering the Beagle, it might last an hour or

Looks good!