dcj123 wrote:
I believe the change is current is only advertised for charging stuff faster, I would imagine it maintains backwards compatibility by never drawing more the 500 mA on USB 3.0 devices that are USB 2.0 compliant. For example if you have a 2000 mA battery, you can charge it at any current between 1 mA to 2 amps and charges slowly or faster depending on how much current. I am thinking the change in current only applies to things that can also take a lower current.
dcj123 wrote:
In the USB 1.0 and 2.0 specs, a standard downstream port is capable of delivering up to 500mA (0.5A); with USB 3.0, it moves up to 900mA (0.9A). The charging downstream and dedicated charging ports provide up to 1,500mA (1.5A)Source -
https://www.extremetech.com/computing/115251-how-usb-charging-works-or-how-to-avoid-blowing-up-your-smartphone Actually, I've been doing a bit of wiki digging and it appears those current values are max ratings on data transfers. The big difference between USB 3.0 and earlier usbs is that it has 5 extra pins dedicated for "SuperSpeed" USB transfer. Logically, if a USB 3.0 device were to be connected to a USB 2.0 port (or vice versa) those extra 5 pins are not connected to anything and thus the device would be utilizing the standard middle data pins out of the original 4 pins, which would then be drawing the lower currents of USB 2, but if a USB 3.0 device is connected to a USB 3.0 port, it then has those extra pins available to it, meaning it defaults to those as opposed instead of the older data pins, drawing more current as a result to maintain those higher speeds.
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Your neurodiverse (Aspie) score: 91 of 200
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You seem to have both neurodiverse and neurotypical traits