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Let's be given a laptop and a single USB controller. Now if one wants to use multiple devices, one has to plug in an USB-HUB and then plug everything into it, for example Gaming controllers, cameras, memory sticks etc.

AS I see it all devices and my laptop make a closed circuit, the devices may simple be viewed as resistors. I am now worried that my laptop might take damage from "overusing" an USB Port or not all devises work properly. Might this be the case here? How do I find out, if it is save to plug in a certain amount of devices? Plugging in which devices is safe / not safe?

Any comment / answer is appreciated.

Imago
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Any well designed USB port will have overload protection. If you attempt too draw to much current, it will shut down to protect the port. Of course, at that point, all the plugged-in devices stop working.

That's why many USB hubs come with a separate power supply - to take the load off the computer.

Simon B
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  • It's a requirement according to the USB specification. Some low end devices cheat on this though and slap on that USB logo anyway. You should be able to decrease tge load impedance on any laptop USB port all theway down to short without long lasting effects. – winny Dec 21 '16 at 17:16
  • Read this: http://www.usblyzer.com/usb-topology.htm The USB topology is a star and there are two separate considerations. .... 1. Power here the load is in units of 100 mA, and for most ports you consider the max as a load of 5 units = 500 mA. Many ports will support more either by default or by negotiation from the devices. Hubs can be powered or unpowered. If unpowered, the host limitations apply. If powered than it's what the Hub can supply, some will allow up to 2 A. ... 2. Path to leaf data timing restrictions, where the standard allows for up to 7 layers and 127 device connections. – Jack Creasey Dec 21 '16 at 19:12