DCA said:
| What is the maximum current or power which the USB specs say can
| be drawn from a USB port?
500mA I believe
Or 100mA for:
- a downstream port on a bus-powered hub,
- a port on a root port hub on a battery-powered system (possibly), or
- a downstream port on a battery-powered self-powered hub (possibly).
And, as noted by another poster, this is at 5V, so the maximum power is 2.5W
(500mA) or 500mW (100mA).
Alex