Comments on: Solar backpack ipod/usb charger

By: Jenny

Jenny — Fri, 25 Dec 2009 12:34:11 +0000

is it possible to get a solar phone charger for a lg phone (specifically lg vx9800 and chocolate)? where can i find one?

By: Jason

Jason — Wed, 02 Apr 2008 08:31:55 +0000

Thanks for all the input. As I tried to make clear, i am no electronics guy, I just want an ultralight iPod charger to go with me backpacking and I really appreciate the feedback. Now, how do I do that voltage divider business?

By: pyrex

pyrex — Thu, 01 Nov 2007 00:18:14 +0000

This circuit will not charge an Ipod. Perhaps a nano or shuffle, but not a bigger ipod.

As was stated by comment 9, you need to get a lvdo regulator and probably 1uF caps between Vin and ground and Vout and ground.

Now you have a steady 5V supply for your USB, but your ipod will still not charge from this circuit, you need a voltage divider. I don't know how to post it here, but if you take apart any USB ipod charger, the voltage divider is there.

This being said, it's probably much easier to buy a higher voltage panel, regulate down to 9V (anything from 9V-12V is fine) and charge directly through USB or firewire, as the ipod's charging circuitry will automatically begin charging from this voltage without any handshake/voltage divider. However, you won't be able to charge any other USB devices from this charger.

By: Chris

Chris — Sun, 05 Aug 2007 16:49:15 +0000

Welllll…. I figured out the problem. The picture he uses is ambiguous as to where the leads to the regulator go (or the panel is backwards from his and the manufacturer’s instructions). I ended up just having to switch the input and output wires and it all worked out, after I bought it outside for a full sunlight. It works. Sorry for the panic.

By: Chris

Chris — Sun, 05 Aug 2007 01:23:46 +0000

I bought the solar panel, the usb female adapter and the voltage regulator, precise as he listed… I built the device. It doesn’t work. I’m a new, for sure, in soldering and building this stuff, but this is a pretty simple project and based on a friend’s recommendation, I tried it. It just doesn’t work.
Worst, I can’t figure out how to email the author for advice as to why it might not. I’m sure I must have done something wrong.

By: bidomo

bidomo — Fri, 09 Mar 2007 09:53:40 +0000

Hey guys!

I can find only the solar panel in the 400ma versions, what can I do to use this one instead of the 100ma one?

By: Jody

Jody — Sun, 07 Jan 2007 16:17:18 +0000

This is my first visit to this site. Pretty cool. anyone know of a version of this that uses a hand crank like those wind up flashlights to charge a usb device. The solar panels are great but I need an option for use at night.

thanks,

By: Tom

Tom — Wed, 13 Dec 2006 04:45:15 +0000

I like this concept. The thought of being able to listen to my motorola V360 iTunes (1000 song hacked version) or play a game or video if I want while in the bush makes me want to make one.
If the voltage is stable who cares usb is usb. The right voltage regulator would make all the difference for me. Mybe he could use laminating film to seal it instead of packing tape.Good hack

By: Richard

Richard — Fri, 01 Dec 2006 04:25:41 +0000

C'mon guys! Ok... So I am a total newbie, but I thought this project was great! I actually was able to understand something out of it - and is giving me interest into all of this!

I think the article is good and that more of these "SIMPLE" projects are welcomed! Then, we can share ideas and improvements!

And please! keep it always very cheap, very understandable (as this article is!), and positive!!

Thanks!

By: devoinregress

devoinregress — Thu, 30 Nov 2006 22:52:19 +0000

Why not use the firewire power instead of USB? All you have to do is switch two wires to the dock connector. USB is fine I guess but it can be flakey (especily with RockBox)

By: MrGoodBytes

MrGoodBytes — Thu, 09 Nov 2006 01:30:01 +0000

or he could've just bought a solar powered backpack

http://www.voltaicsystems.com/

or do what I did and win it from treehugger.com for a DIY contest

By: unjust

unjust — Mon, 30 Oct 2006 19:30:09 +0000

so ironically the company he bought the solar panel from sells the same thing. http://store.sundancesolarcorp.com/sosochforipc.html

not that it's not inherently more fun/cheap/lighter to build it oneself, but clearly there's some research skills lacking.

By: uski

uski — Mon, 30 Oct 2006 00:09:42 +0000

I am quite afraid by what I'm reading here.

1) NEVER EVER charge a Lithium battery without the proper charging circuitry. Li-ion and Li-po batteries are extremely susceptible and they _WILL_ protest if you charge them incorrectly, sometimes by catching fire at an unexpected moment.

2) Using a 7805 off a 6V panel is stupid as common 7805 have a drouput voltage larger than 1.5V, which means that you'd need a stable 6.5V (min) at the 7805 for it to deliver a proper, regulated, 5V output. To do things professionnally you'd need a flyback/SEPIC switching power supply that generates a 5V only when the light is sufficient.

3) Feeding your iPod or [insert your favorite MP3 player model here] by some unregulated voltage may harm it, especially if the voltage gets higher than the rated power supply nominal voltage.

By: asdf

asdf — Sun, 29 Oct 2006 20:33:22 +0000

funny how he says he cant find a solar ipod charger, yet if you search "Solar ipod charger" in google the first link leads to this:

http://www.solio.com/v2/index.htm

its even compatible with the nano.

By: Wonko The Sane

Wonko The Sane — Sun, 29 Oct 2006 19:52:46 +0000

Err, Not the best circuit, the 78M05 is not the best for this circuit – it requires about 2V more to regulate – e.g. at least 7V to give 5V out….

What is required is a LDO (Low Drop Out) regulator also a few caps on the circuit would make it more stable e.g. 10uf 16V, and 10nf on the input, and the same on the output (Yes, 2 Caps for each, 10uf smooths the supply, and the 10nf remove the High frequency instability)

Nice idea…