Batteries Power Supply

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1

Hi,

The project I'm working on is going to use a beagle board and 2
webcams (no zoom or anything electro-mechanical). I need to be able to
use this without being plugged into a power outlet for maybe 15
minutes or so at a time.

I was wondering what sort of battery and portable power supplies have
you guys used or could recommend? Perhaps some of the people using the
beagle board for robots would have a good suggestion.

Thanks for your help,

Mike

2

Personally I use a combination of:
(a) a USB power adapter, i.e. mains → USB. There are hundreds available and you can get cheap ones for around $5. Google for: “usb mains adapter”
(b) a USB rechargeable portable battery - ideally powered by USB - i.e. USB (for power) → internal rechargeable battery → USB (to provide power). Again there is quite a selection to choose from at around $20. Google for: “usb portable power battery”

Main reason is that (a) and (b) are re-usable for other devices and the cost is low compared to non-USB prebuilt solutions. While a bit more expensive than “build-it-yourself” its also a lot less hassle.

You almost certainly don’t need more than 1A of juice for your project (300mA for board, 200mA for each camera). That’s fortunate as that’s what many of those (a) and (b) devices are rated for… but definitely check that its not something pathetic…!

3

Thanks for your help Michael. One follow up question though. I thought
I read somewhere that usb can only source 500mA so would I need to use
2 of those things or is there some way to get around that limitation
and use only 1?

thanks,

Mike

4

I read somewhere that usb can only source 500mA so would I need to use
2 of those things or is there some way to get around that limitation
and use only 1?

Using four NiMH AA batteries (1.2V x4 = somewhere near 5V), I was able to run for a few minutes the Beagleboard (up to 400mA) and the DLP Pico Projector (more than 900mA) on the same battery pack (those AA batteries were rated “2600mAh” but this is more a manufacturer opinion than a real field figure).

Alfonso

5

The official spec for USB 2.0 states that initially you only get 100mA and that you are supposed to inform the host how many power unit (each of 100mA) that you need before powering up to full. However, this is rarely enforced these days and lots of devices happily take more than 500mA if the host is willing to provide it. (e.g. most USB DVD burners will happily burn if it can get sufficient current from the host, otherwise it will only allow read)

I’ve tested the BeagleBoard and it happily runs upto 700mA worth of peripherals on the EHCI port while being powered through the OTG port. Including the boards internal needs this means a total of 1A can be drawn from the OTG port (presumably also applies to the barrel connector although I never actually tested that). Checking the schematics and parts the silicon devices are all rated for that so no worries there either.

6

Hello World

will this work for the beagleboard:

http://www.bixnet.com/5v7libapa.html

Bat-PM55-withCellPhone.jpg

7

Hello World.

*//will the ryobi 4v battery device with usb work on the beagleboard//*

chris

8

You need to make sure that if you are using USB host, that the 5V is there through the life of the battery. If it drops, then the USB may not work. I think this should be OK.

Gerald

Bat-PM55-withCellPhone.jpg

9

Gerald,

Can I use that as the main power supply. NON-HOST I NEED A STANDALONE

thanks,

chris

10

Yes. The requirements for the 5V supply can be found in the System Reference Manual. http://beagleboard.org/static/BBSRM_latest.pdf

Gerald

11

I would need to see a datasheet.

Gerald

12

Gerald,

here is the information you requested.

Ryobi Introduces the Tek4 Portable Power Source powered by the Tek4 4V Lithium-Ion battery technology. This tool offers a number of advanced features such as: Weather Resistant for the rough environments, compatible with multiple electronics for versatility and is packed with multiple adaptors for cell phones, blackberry’s and iPods. This Portable Power Source from Tek4 Innovation is the perfect tool for those who need immediate back up charge for their electronics. The Portable Power Source is backed by Ryobi’s 2 year warranty.

  • Up to 80 hours audio time per charge

  • Convenient power for charging common electronics: blackberry, cell phones, and iPods

  • All the power you need on the go

  • Dust and weather resistant

  • MFG Brand Name : Ryobi

  • MFG Model # : RP4900

  • MFG Part # : RP4900

  • Assembled Depth (In Inches) : 4.08 In.

  • Assembled Height (In Inches) : 9 In.

  • Assembled Weight (In LBS) : .23

  • Assembled Width (In Inches) : 2.2 In.

  • CSA Certified : No

  • Color / Finish : Black/Green

  • Cord Length : 0 Ft.

  • ETL Safety Listing : No

  • Length : 4.08 In.

unknown.jpg

13

Gerald,

RP4900_659_tri.pdf (695 KB)

14

Based on this information, I would say no.

Gerald

15

Gerald,

Can you provide me with a battery power supply that will power the beagleboard as a standalone unit.

Thanks,

Chris

16

All you need is a 5V output with a battery source. The $79 one you found will work as I have previously stated. You can also use numerous ones that are out there that supply a 5V output from a pair of Li-ION AA batteries. This can be connected to the USB OTG port and power the entire board.

Gerald

17

http://www.frontierpc.com/productDetails.aspx?eId=1010130125

18

Gerald,

Where can i buy a beagleboard with 4gb of POP pre-installed and a 7
inch touch screen pre-insalled as well.

.

Chris

19

Nowhere that I know of. 4Gb parts are not in production yet and I have no idea where to find a 7 inch screen dedicated to Beagle.

Gerald