Hi,
I'm working on a portable solar project designed to charge multiple (3 or 4) USB devices concurrently. My solar array is producing around 7V @ 3.5A. Using off-the-shelf eBay circuit boards I'm able to charge multiple devices. But as soon as a cloud passes over or something blocks a portion of my solar array, some devices (namely iPhones) stop charging.
To fix this problem, I would like to include a battery with charging circuit just to keep the power steady during these short periods when the solar power drops below USB levels. I can find lots of battery charging circuits and DC-to-DC boosters, but they all seem to max out at 1A input and only feed the boosted battery power to the USB ports. This seems like a big waste of power since the array is producing 3.5A.
My question is, how can I use the full solar current when it's available and only supplement with the battery when needed?
Thank you in advance for any help you can offer.
I'm working on a portable solar project designed to charge multiple (3 or 4) USB devices concurrently. My solar array is producing around 7V @ 3.5A. Using off-the-shelf eBay circuit boards I'm able to charge multiple devices. But as soon as a cloud passes over or something blocks a portion of my solar array, some devices (namely iPhones) stop charging.
To fix this problem, I would like to include a battery with charging circuit just to keep the power steady during these short periods when the solar power drops below USB levels. I can find lots of battery charging circuits and DC-to-DC boosters, but they all seem to max out at 1A input and only feed the boosted battery power to the USB ports. This seems like a big waste of power since the array is producing 3.5A.
My question is, how can I use the full solar current when it's available and only supplement with the battery when needed?
Thank you in advance for any help you can offer.