I'm not quite sure how your 770 charged through USB. That's impossible by all my knowledge, unless you followed the guide here on how to charge via USB. There is no power going to the USB hub, you would have to solder a connection from the USB to the battery. Please see this. http://www.internettablettalk.com/fo...Charge+USB+770 Do not buy these if you just want to charge you device. Sorry bout that.