Submission + - Why do some devices refuse to charge via USB? (no)
kriston writes: I have lots of MP3 players, mobile phones, video devices, and game controllers. All of them can plug into USB sockets, but a curious few simply refuse to charge. The chief offenders are Motorola phones, Creative MP3 players, and most annoyingly, the Sony PlayStation 3 controllerss. Simply putting +5V at 500 mA on the port is not getting these things to charge. What is the magic secret ingredient these chargers have that make these USB devices start charging?