Wish for 2nd generation Neo: USB 2.0

Harald Welte laforge at openmoko.org
Sun Jan 21 15:38:12 CET 2007

On Sun, Jan 21, 2007 at 06:56:30AM -0700, Joe Pfeiffer wrote:
> Harald Welte writes:
> >
> >The main problem (with more powerful SoC) is not to provide a USB2.0
> >host port in the device.  The main problem is power.  You need a pretty
> >powerful DC/DC step-up converter to provide the 5V power supply to the
> >USB bus.  And you have to provide at least up to 100mA - but to support
> >all devices, 500mA.
> I don't see this is a real problem -- 1.1 is supposed to do that too.
> I'd have to look at the specs (USB and USBToGo) but I don't think
> unpowered USB is actually compliant under any of them.

It's not a technical problem per se.  

It's just that you have to have one extra (powerful) DC/DC step-up
converter in the device, something that vendors of phones (and other
devices) usually don't put there for cost, battery life time and PCB
footprint reasons.

- Harald Welte <laforge at openmoko.org>          	        http://openmoko.org/
Software for the worlds' first truly open Free Software mobile phone

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