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Requesting more current from USB bus?

Posted: Mon Jul 16, 2007 5:37 pm
by nauht
Hi,

I'm thinking of creating a USB decoration device - Wii "sensor" bar - and I've calculated that for 8 IR LEDs (2 x 4 in series, with the two groups in parallel) that I would need 250mA @ 5V. Since USB initially provides only 100mA, I'm thinking of using AVRUSB to request more amperage. Now I'm wondering if I do request more current, would it damage the AVR? Oh, and how much current does a typical AVR require?

Thanks.

Posted: Fri Jul 20, 2007 6:51 pm
by christian
All you need to do is to specify your current requirements in the device descriptor. There's an option in usbconfig.h where you specify the power you need from the USB.