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USB Li-ion charger Help

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Newbie level 3
Aug 13, 2007
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This'll be my first time working with lithium batteries, so I want help so that I don't catch my house on fire, that being said I need you guys to help me make a schematic.

Can someone check this schematic for me, I want to use the max1555 chip and the UCC3952 chip because I already have them.

In the end there'll be 2 sets of these chips charging from 1 usb port. The batteries then get boosted up to 5v (hooked in parallel and then using a boost converter) and have an aoutput usb port the same as the input usb (to charge you need a male to male adapter. So basically it's a rechargable USB battery pack that has 1 usb port. It'll have a total of 4800 mAh and have the dimensions of about 3.2"x1.4"x0.7". It'll probably be able to charge a video ipod 4-5 times on one charge.

1 last question: The DC pin of the max chips are internally limited to 300mA, the USB pin of the max chips are limited to 100mA, since 2 would be charging in parallel from 1 usb port can I use the DC pin and each would either get 50mA or 250mA (depending on whether it's a low power or high power usb)?

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