Power up board from 6 volts?

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1

Hi, guys

Is it safe to power up board (bone & beagle) from Pb power source with
6V output?

Thanks.

2

http://beagleboard.org/static/beaglebone/latest/Docs/Hardware/BONE_SRM.pdf

section 3.0, table 2

and

section 4.8

3

Beagle:
if you don’t use USB devices powered from a board then it’s fine. Main LDO will swallow it

Bone:
don’t know, but probably yes if a overvoltage suppressor allow it.

2012/9/27 Eric Fort <eric.fort@gmail.com>

4

Are you trying to use Beagleboard batteries? Maybe you should use rechargable batteries. Their voltage output is significantly lower than 1.5V so that if you use four rechargable batteries in series, you should get a voltage closer to 5V but I am not sure if it would be within tolerances. Beagleboard XM (only XM) documentation says it has over voltage protection. A red light comes if there is a problem.

You may also want to use a three-terminal voltage regulator known the 7805. One pin receives 6V in. One pin is 5V output to Beagleboard. The third pin is connected to earth. It is a simple as that and the 7805 is good for 1A. Some manufacturers are selling a version called LM7805K which delivers 3A, the maximum current that a Beagleboard is expected to consume with lots of peripherals connected, I think. The datasheet can be seen here:
http://www.fairchildsemi.com/ds/LM/LM7805.pdf

Please be sure to check voltage and polarity with voltmeter before connecting Beagleboard.

Ahmet