I have a small desk fan that is currently powered by 4 AA bateries, I have measured the voltage output and it is 5.5VDC which got me thinking. Is it safe to modify the fan to run off a USB port on my PC?
I'm not sure if the fan draws more than 100mA, but it is my understanding that USB will only allow me to draw 100mA by default anyway. Is this correct, or could my fan draw too much power?
I also read this
A dedicated charger can supply maximum 1.8 A of current. A portable device can draw up to 1.8 A from a dedicated charger. The dedicated charger shorts the D+ and D- pins together disabling data transfer and will not send or receive any information, allowing very simple, high current chargers to be manufactured. The increased current (faster charging) will occur once the host/hub and devices both support the new charging specification.
Is this supported by USB 2.0, or will this not be supported until 3.0?
should I short the data wires in my case or just leave them disconnected?