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Would this circuit work for a basic solar USB charger? Answered

So i'm making this solar powered usb charger, but i don't know too much about circuitry. I was reading around and drew a circuit in mspaint : http://img12.imageshack.us/img12/5403/circuitr.jpg. I'm just asking if this  would work to charge the usb and the batteries(then the batteries charge the usb with no light). I also know that i need two diodes, one to prevent the batteries from discharging, and one to regulate voltage for the usb  connection, could someone point out which these are?

I'm using this solar panel: http://www.dealextreme.com/details.dx/sku.17439
But dealextreme has sketchy quality stuff, anyone know a safer place to buy a solar panel of like specs? Like amazon? or Radio Shack?

After further inspection i realized that the black cord of a usb cable is ground. I'm not sure if that's right. How would the connection to the USB work?


That circuit will destroy anything connected to the USB You need a regulator for the USB connection. Try an LM7805. Steve

That would work without any other components yes? Just connect input and output, then ground goes to the negative wire on the solar panel?

Yes, but you still need the blocking diode to protect the panel. Steve

There's a recent post at Adafruit about that sort of thing. They include a schematic for their charging circuit, sell the solar panels, mention hooking it up to a regular Mintyboost, etc.

I'd rather not buy a premade circuit, and making one of those is too complicated for me.