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USB Power


#1

Hi, I would knew how much power I can get out of the usb port on a FEZ Cobra? Under windows my umts stick needs 500 mA.

Best regards


#2

You are probably confusing the 500ma value - USB has a maximum of 500ma supply, and you would probably find that your device consumes much less. I would expect that a USB host like Cobra, with sufficient input current capability, will be able to deliver your 500ma. But you may find that there’s no simple quantitative answer here, it will totally be dependent on your input power source and the conversion that it undergoes, as one of those is more than likely to limit the possible current that can be sourced through the system.


#3

Cobra has a fuse on the USB that will limit output… check the schematic but I think is was around 500mA.

Of course your input supply must provide that and the Cobra linear regulators are not good at providing a high current… they get hot… so I wouldn’t probably suggest pulling that much.