Power supplies for Xm


I'm looking to house my Xm board in a case and was wondering about
internal power supplies. Can I safely use a PSU that has a 5V rating
greater than 3A, say a mini itx PSU? I also have an old external drive
enclosure with a 2A PSU. Would that be better than a mini-itx supply
or no difference?



Current ratings are only a limit on the low end. A 3A supply is fine and if you plan to load the USB ports, actually a good idea. Just make sure you have the correct polarity on the power connector and that the supply is actually 5V and well regulated.


Just related to the BeagleBoard power supply, can somebody direct me
to a place from where I can buy a batter pack to run beagleboard with
USB ports. Is it available on Digikey ?


There are currently no battery packs per se out there. Based on your specif iced needs, I wouldn’t even know where to start. IF I assume that you want to fully uses the USB ports, you are talking 10W just in USB power alone and that is use in one hour. So, if you can closer define your power requirements, you may be able to put a solution together. A LI-ION battery pack is 3.6V, so you cannot get the 5V out of it for the USB, so you need a boost converter to do that. There are some cellphone style battery to 6V devices out there and they will work over the USB host port, but hat will not get you power to the USB Host ports. Not knowing your actual battery requirements, it is not possible to know if it will work or not.

If you can provide more detail as to your needs, it may be possible to figure something out.



Sorry for the abstract details.
I am planning to power up the BeagleBoard xM with just one USB webcam
hooked up, and this for testing purpose only, no serious deployement,
I don't plan to run it for any longer than 30min-1hr.

If we use 4x1.5V alkaline battery with a regulator, will it work ? I
am not a electronics person so I don't know much about regulators and
all but I saw in some blogs and videos people powering up the BB with
pencil cell battery pack.

Any recommendations on that ?
Also, It would be a good idea to start shipping battery pack along
with the BB board (with different Amp ratings for different power


I would look at using 4 Lithium rechargeable batteries instead. They can supply more current and are easily rechargeable. A plane linear regulator should do the trick. If you used a boost converter, and you should be able to buy test or EVM board for these, you could use less batteries or even put them in parallel to give it a boost in run time.

As to shipping battery packs with Beagle, we have shipped 25,000 boards. You are the first person to make such a suggestion so from a business standpoint it doesn’t make a lot of sense. That is not to say there isn’t a place for someone to make an add-on battery pack board, but to date, no one has come forward with such a solution…


Something like [1]?

[1] http://www.liquidware.com/shop/show/BB-BJC/BeagleJuice

This was made for the Rev C4 and not the -xM. It should work for the -xM but I don’t know if it has been tested on the -xM. The C4 has one USB host port while the -xM has four USB ports which will need more power.

A HD can take a lot of current, so check the current and see if a single USB port supplying 50 mA is enough. 600mA won’t even begin to scratch the surface of powering a board and a HD.