USB device connected to USB 3.0 Hub - current question


kuru

Laptop und Trachtenjanker
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Hey guys!

There's an HDMI stick PC I'd like to run off a powered USB hub.

USB 2.0 hubs deliver a maximum current of 500mA. To reliably run the stick PC I'd need about 800mA, which I'd get as per USB 3.0 spec - up to 900mA.

Q: Will a USB 3.0 hub expect some sort of identification signal from the PC's micro USB power jack and thus fall back to 500mA?
 
Hey guys!
Will a USB 3.0 hub expect some sort of identification signal from the PC's micro USB power jack and thus fall back to 500mA?
I think that no one can give you a definite answer to that as in the end, it depends on how its actually implemented.
While power negotiation is different between USB 2 and 3, if the hub detects that its a USB2 device and goes into backward compatibility it may only deliver (or better limit its output to) 500mA as per specification, or just uses the "reserve" it has due to its USB3 compliance.

Edit:
Do you know someone with a newer, high range Samsung cellphone? I have a Samsung Note 3 and I think its power(plug) supply delivers the full 1.5 A regardless of the connected devices USB version, as my wifes mobile phone (USB2) charges a lot faster then with its standard power supply (which already delivers 800mA according to its specs)

Edit #2:
I found this on the subject, they sell powered USB hubs, and they look rather "beefy" to me
 
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I suspect many cheap USB2.0 hubs don't actually regulate current to each device independently - that is, a 4-port hub might be rated for 2A total over all outputs, even if one output has a higher-power device connected and the others are unused.

Never actually tried it though.
 
Thanks a lot for the input!

I think that no one can give you a definite answer to that as in the end, it depends on how its actually implemented.
I feared that answer : )
I have a Samsung Note 3 and I think its power(plug) supply delivers the full 1.5 A regardless
Same phone here, my plug says 5.3V/2.0A. But yeah, it's not a hub, but a power supply and thus may just behave differently.

Edit #2:
I found this on the subject, they sell powered USB hubs, and they look rather "beefy" to me
Their prices for EU are crazy o_O
I'll get this one - it says it has a fast charging port that delivers up to 2.4A, that may just be what I need.
Nevermind, needs a 12V power supply for itself :-/


Maybe I'm just terrible at planning this. There must be a smarter way to do things.
I wanted to run the HDMI stick and the screen off a two-port portable powerbank AND connect a USB hub to the stick for peripherals. The stick's USB jack though delivers so little current that I need a powered hub, there's no way around.

I could get two of those powerbanks, that won't break the bank (heh). Still buy four Li-Ion 18650s, but two battery holders and split them up. Then I'd have four ports available internally. The power banks would have less load, produce less heat etc. Then I can just use any old powered USB 2.0 hub and be done.

Edit: Attachment below is old plan. Goshdarnit I love doodling things on the Note : D

PC Box_2.jpg
 
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