From: Jan S. <jan...@vo...> - 2009-01-24 23:11:08
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Jason Stahls napsal(a): > Jan Smrz wrote: > >> Our miniLA is using linear regulator therefore it still sinks 700mA at >> 5V side. Even if it was 500mA then it would be problematic since one USB >> port is able to provide at most 500mA (with respect to specification). >> However you could try to supply miniLA from two USB ports as can be seen >> at some external hard drives. >> > > Can you still pull the full 500mA off a port without having a device > enumerated on it? I seem to remember there being some low-power mode > that the ports ran under till enumeration was complete... > > Thanks, > > Jason > > It is as you expect - full 500mA can be drawn only after enumeration. Before enumeration it should be below 100mA. FT2232 has a support for it (pin PWREN#). Jan |