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Anyone know how this standard actually works? I think right now Android phones tend to short the data lines and Apple uses some system of voltages to communicate that it's high power, which means that the other device usually gets stuck pulling 0.2 amps. How does this new standard tell the device it can supply 100 watts? And does this mean that iOS and Android will be stuck on 0.2 amps? Can you plug a legacy device on at all?


http://www.usb.org/developers/powerdelivery/

USB has both power and data lines. This new standard can use data lines to negotiate power delivery, I believe. I'd expect will still be backwards-compatible of course. I would think the only allowable voltage would be 5V, as is currently.


Correction: the new standard will always start at 5V (for legacy purposes), but then may renegotiate the voltage (and current), according to: http://www.usb.org/developers/powerdelivery/PD_1.0_Introduct...


100W at 5V would be a 20A current, which is sort of high.

http://www.usb.org/developers/powerdelivery/PD_1.0_Introduct... Page 9. There will be different voltage levels: 5V, 12V, and 20V.


yup, I had read that and corrected exactly same time as you :)




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