Hi Guys,
With reference to the following product: https://core-electronics.com.au/usb-type-a-female-breakout.html
Would I be able to connect the data lines via a Raspberry Pi’s GPIO headers, and connect VCC/GND from an external and stable 5V power supply?
My intention for this is because it appears my Pi is not capable of powering the last peripheral I need for my system, and I thought I could instead provide ALL the power for the cable from elsewhere. I am having problems with using an externally powered USB hub due to USB suspension which is why I do not want to use one.
Cheers
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Hi Samuil,
Yeah definitely, just make sure sure you have the ground between the supply and your Pi tied together.
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Yes to powering it externally, but not connecting the data lines via a Pi’s GPIO headers as there’s no USB interface available via the GPIO: https://pinout.xyz/
If you only need the one USB device once its all setup it shouldn’t be an issue as Linux only enables power management if there’s a Hub connected, not if it’s just a device.
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Thanks guys,
Also Oliver, what would be the correct process for connecting the data headers on the break out board if there is no USB interface via the GPIO pins?
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Hi Samuil,
Oops completely missed that bit, you would have to tap into the D- and D+ pins on the inside of the USB port.
Another way to do this might be to grab a few USB extension cables, splice them open and solder the wires directly in.
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Thanks Liam
I think this is a little too difficult for my application if that is the case but thank you so much for breaking it down for me. Reason being I took at look at the PCB and it is so tiny I am guaranteed to bridge a million lanes in the process 
To give you further context, I have a USB 2.0 active extension cable (10m) which I am trying to connect directly into another device back to my Raspberry Pi.
Would it be possible for me to connect the extension cable (as standard i.e. Pi to device) but expose the power wires and connect them straight into an external 5V power source? Basically an attempt to have a USB cable which is not powered by the USB bus at all, instead externally powered.
If it would work, which ends of the power cable would I connect to the external 5V supply i.e. downstream to the device, upstream to the Pi, or both? I would assume not both since I presume there is no reverse current protection in the USB port on the Pi.
I already tried something similar with one of those dual USB cables that allow you to take additional power from the USB bus, since the second cable is strictly power with no data wires (attached image below):
I cut the second Male USB which only had power wiring and connected it to the external 5V supply. With this method I did see my device finally start to recognise and work (since it finally did not exceed the Pi’s USB current limit as soon as I started operating the device). I cannot resort to this though because it won’t work with the USB extension cable connected into it, which is why I am wondering if the above method would work so I can just use the extension cable.
Cheers!
Edit: I marked this up to keep it simpler:
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Yep, I see no apparent reason that shouldn’t work - although… you did say it’s an active extension cable, which means there’s a little PCB hidden inside it somewhere to boost the signal. You’ll want to make sure you retain power to this and don’t cut it out.
That said, I have a vague recollection of USB 2 being capable of 10m, and 3.0 being limited to 5m. If it’s a 2.0 device, you might not need the signal booster (double check this first before relying on it).
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