Question what is the Difference between powered and un-powered connectors

I guess that question is more about USB hubs than just plain connectors which are all same for given standard.
Explanation is easy, Powered HUBs receive power from external 5v adapter and not from USB port HUB is connected to. USB ports have limited power output depending on their generation and each port shares data bandwidth and power with all devices connected to it. If your sum of devices or one device in itself exceed the power of a single port, you have to give it power from another source to compensate for it.
Another example is using USB adapter to connect HDDs, some, 2.5" drives may require more power than single USB port can provide so have to be connected two two USB ports at same time (the other connector is only for power, 5v) or to external power source.
Other example would be connecting a 3.5" HDD which also require 12vDC as well as 5v, USB doesn't have 12v source so yet again external power which has both voltages is required.
Than there's USB2 limitation of cable length to about 5 meters after which it starts loosing power due to resistance and low direct current voltage. In that case more power has to be added and over 10 meters data leads have to be amplified.
 
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ok for example if i have USB micro B for external SATA, why is there two connection?
CountMike
One USB2 port can supply maximum of 100 mA, or 150 mA for SuperSpeed devices and makers of that external disk clearly know that it's not enough so they provided another USB connector for power only, no data wires connected. Size and type of connector are not important.
It must be adapter for only 2.5" drives as adapter for 3.5" drives would .have a Molex or other connector to supply 12vDC too. If it's not there that means it's meant for 2.5" drives only. If you were to connect an SSD to it, you probably wouldn't need second USB connector as SSDs use much less power.
If you linked me to that adapter, I may be able to provide more.
This is an example of 2.5" drive USB2 to SATA: https://www.amazon.com/SATA-22Pin-A...coding=UTF8&psc=1&refRID=CPP738VXE2GBFPBF0YKA note that SATA side is in one piece with no 12v adapter.
This https://www.amazon.com/SATA-Adapter-Cable-Power-Cord/dp/B001OOT804 is an example of USB2 to SATA 3.5" but also for IDE type HDD adapter.
 
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RayOfDark

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May 16, 2019
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The jumper blocks on SATA HDDs can serve different purposes depending on the manufacturer. Some drives allow jumpering an SATA-3 drive down to SATA-2 for improved compatibility. Others on some RAID-optimised drives can be used to provide staggered spin-up to reduce peak current requirements on startup.

There may be other features that can be enabled/disabled by jumper but, to the best of my knowledge, the two above are the most commonly used.
 

Abs2428

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Mar 17, 2019
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If you are preparing for a presentation on these topics (which sounds suspiciously like homework to me), then you should be undertaking the right effort of researching the material yourself, instead of asking people to provide the information for you.
hmm thats right but i did my research regarding that
thsnk you dude
 

InvalidError

Titan
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One USB2 port can supply maximum of 100 mA, or 150 mA for SuperSpeed devices and makers of that external disk clearly know that it's not enough so they provided another USB connector for power only, no data wires connected. Size and type of connector are not important.
The 100mA limit is only for uninitialized devices. The actual per-port limit is 500mA even in USB1 and got bumped to 800mA for USB3. And now we have Type-C which allows up to 20V 5A.
 
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