Power Controller for a USB Solar Charger

The first thing I would try is one of the "automotive" types of phone chargers. They are designed for 12-14V, but some of them may just work down to 7V. If the panel really does output 7V@1A, it may have a higher voltage with a lower load.

There are other "modular" types of DC-DC converters that will do this as well, but they won't be as cheap or available as the run-of-the-mill car chargers.

Your location may determine the best solution, as well, are you located in the U.S. ?

Tom D.

I am located in the UK.

http://www.mouser.com/Search/Refine.aspx?N=254455+4294853839&No=125

I do not understand french. Were these voltage controllers?

Yes, those are the DC/DC converters I was speaking of. Where does French come in? The link took me to Mouser's website. There are only a few parts there that will give you 5-5.5V with only 7V in, and they start out around $20, cheaper to try a car charger first, you probably already have one sitting around?

Tom D.

I have a freeloader solar charger. I was thinking of connecting the solar panel to that and plugging in my phone at the same time. It says in the instructions that you should not charge the freeloader and use it at the same time, that is why I am needing an alternative.

Why bother with the Freeloader at all when you have the larger panel? If you get the right converter, just go from the larger solar panel to the converter, to the phone. Leave the freeloader out of the loop. Set the Freeloader in the sun too, and then use it charge the phone when the sun isn't shining.

Tom D.

For some reason your connection defaulted to French. There is a "change country" button in the upper right, probably with a French flag... change to UK...

I just picked up a 12vdc to 5.5 vdc usb converter from Amazon for $2.00 (USD). I'm guessing 7V is too low for a 12v converter though... do you have a second panel to run in series?

I have two solar panels. I have a pathetic 6 volt freeloader supercharger which gives out a puny 10ma at 6 volts. Absolutely useless for anything other than tricle charging small batteries. My other panel was 3.4v and produced 2.3 amps. I then cut it up and changed its configuration to make a 7 volt panel that gives out just over an amp.

Sounds like you are looking for a voltage regulator. These can be found at digikey.

Order a POT or two to create a voltage divider so that you can control the input voltage so as not to damage the regulator.

These are supposed to be step-up (only) S.M.