5.2v Regulator

[viper1]

Hi all, This may have been asked before, but will the Pi run on 5.2v without issues, I have read that it will run on 4.8v using 4 x 1.2v AA NiMh rechargable batteries. however as the voltage reduces it can cause issues. My thought was using a LiPo 7.4v battery (http://www.hobbyking.com/hobbyking/stor ... Pack_.html) connected to a voltage regulator 5.2v (http://www.hobbyking.com/hobbyking/stor ... duct=24752) What are your thoughts please.

Regards

Mike

[tummychow]

That thing costs 25 dollars.... it might work, but it's a ridiculous waste of money. for that price you could buy a huge pile of TO-220 5V regulators and wire them up yourself. If you're not concerned about heat losses, a standard 7805 linear voltage regulator will run smoothly off of 7.4V input and provide the Pi with more than enough current. You could get more efficiency with a switching regulator but that might be a bit too complicated for your solution. Make sure that the batteries can safely push 1A of current; some batteries have a lot of internal resistance and reaaallly don't like having a lot of current drawn from them.

[Dilligaf]

Better off with a Ubec http://www.hobbyking.com/hobbyking/stor ... ction.html

[rpdom]

The recommended working voltage for the Pi is 5V +/- 5%. Which means anywhere between 4.75V and 5.25V. In practice the lower voltages tend to be unreliable, so I'd recommend a minimum of 4.85V.

5.2V should be fine. It's not outside the specs - unless your supply drifts a little higher.

To be safe, feed it 5.2V through the micro-USB, but not direct through GPIO. This way the small voltage drop across the polyfuse F3 will mean you get closer to 5V and should have a stable Pi

But, yes to what Dilligaf said. That's the best option, especially as the regulator you listed is linear and will dump the excess 2.2V (7.4 - 5.2) as wasted heat and a switching UBEC type won't waste much at all so your battery pack will last about 10-15% longer.