digital camera battery charger? I will be in the back country so I won't have access to electricity.

I already have a flexible solar array that can hang from my backpack. I am looking for control circuits that can effectively charge a digital point & shoot camera battery.

My array is 1x2' and puts out 12 volts and up to 400 milliamps at full output about mid-day. I designed and soldered together a regulator to regulate it to 6 volts. But I need something better and more precisely regulated.

My battery is a Li-Ion 3.7V with a 1700 mAh capacity.

Thanks!