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Using the USB data lines in a Mini-PCIe connector?

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Synomenon

Synomenon

Lifer
My notebook (an Acer Aspire 1810T) has an unused mini-PCIe slot. It doesn't even have the connector for plugging a mini-PCIe card in. It does have the traces though that the connector would be soldered to and I have read that the USB data lines are active.

The mini-PCIe traces also have 1.5v and 3.3v lines as shown here (pinout of a standard mini-PCIe slot):
http://www.interfacebus.com/Mini_PCI_Express_Bus.html#b

I want to either:
- dismantle a Logitech Unifying Receiver and connect it to that USB "port" in the unused mini-PCIe slot. USB provides 5v though.
or
- hard-wire a female-A USB port to it.

How would I get 5v to the unifying receiver or a port through just the traces in that unused mini-PCIe slot?


Someone did something similar here, but they cannibalized one of their external USB ports to do it:
http://engineerable.com/2010/05/logitech-unifying-receiver-integrated-into-lenovo-w500-laptop/
 
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Thanks.

What I'm trying to do is place the Logitech Unifying Receiver internally so it's not using up one of the external ports AND isn't sticking out all the time.
 
IsLNdbOi said:
How would I get 5v to the unifying receiver or a port through just the traces in that unused mini-PCIe slot?
Click to expand...

run a wire from the +5V contact on another usb port somewhere on the motherboard?

...you can't do it from just the traces on the mini-pcie slot.

that receiver probably doesn't eat much current, but don't be surprised if you plug in a device to that port that needs a lot of current that the receiver cuts in and out.


was there another thread like this?
 
Several problems to overcome.
USB expects 5V so you would need a dc-dc converter
logic levels on USB are 5V, though 3.3V level can work, it is subject to noise which can cause data errors.
I would open the laptop, solder some wires inside to the USB jack that already exist and route that cable to the compartment where I wanted USB.
 
So it's safe to tap into the 5V line (to power that extra USB port in the unused mini-PCIe slot) from one of the external USB ports?
 
IsLNdbOi said:
So it's safe to tap into the 5V line (to power that extra USB port in the unused mini-PCIe slot) from one of the external USB ports?
Click to expand...

should be fine. the receiver needs the 5v but internally regulates it to 3.3v anyway then uses that for usb signaling ( differential ~0-3.3v ).

i'd worry more about finding space in a laptop for it, keeping it from rattling about, and finding a good location for signal.
 
Don't be surprised when it powers up but won't work. Tapping the 5V rail will be easy but soldering wires to impedance matched data lines may not work out so well. USB, even high speed, runs at a relatively low frequency these days, but it's still a carefully designed circuit. At the very least make sure you use as close to the same length wires as possible when you connect them to the laptop.
 
I've abandoned this project. I've decided to just use bluetooth mice. Now if I could just find a nice, full-sized bluetooth keyboard...
 
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