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Is there a USB Windows 7 driver that outputs a voltage between Pin 1 and 4 of 5 V?

Just like a Charger. Others pins should be open/disconnected.

My notebook is a Lenovo X220.

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You question is a little confusing. In general a USB driver has no control over the port's voltage. What are you trying to accomplish? Is your device not charging with the USB port's driver "as-is"? –  Ƭᴇcʜιᴇ007 Jul 12 '12 at 0:58
    
Correct. Confusing?? Pin 1 and 4, 5 Volt DC, that's it. How to do that? –  jacktrades Jul 12 '12 at 1:06
    
Normally, with a 'dedicated charging port' as per USB specifications, the data pins should actually be shorted. And this kind of thing would likely require motherboard support. I'm not sure if there's some software (e.g. driver) way to supply the max (5 units, 500mA, on USB 2.0) out of a standard port without proper negotiation - I guess it's possible... –  Bob Jul 12 '12 at 1:15
    
I see my charger that doesn't have the data pins, only 2 pins. So other must be open in this case. Thanks :) –  jacktrades Jul 12 '12 at 1:17
    
It should be possible because this is what actual windows usb phone drivers do. –  jacktrades Jul 12 '12 at 1:25

1 Answer 1

up vote 1 down vote accepted

Pin 1 is +5v. Pin 4 is the ground.

According to the user guide (page 8) for the X220, the USB port on the right side just below the Media Card slot is an Always On USB slot, so as long as there is power in the battery and/or the unit is plugged in, that USB slot will provide power to any device plugged into it... regardless of whether the laptop is on or not. That means it is operating system and driver independent.

That is the only USB port on that laptop which will provide an Always On connection.

What is confusing, is why you would feel the need to find drivers to supply power to a USB port that is always going to get power anyway. You see, the other USB ports will supply power to any device that is plugged into them if the laptop is turned on.

For example, if you were to purchase a USB desk fan or a USB desk lamp or even a USB powered heated travel mug and plug one of those devices into a working USB port, there are no drivers to install to get them to work. They will just work. Why? Because anything plugged into the USB port will get power (provided it is either an always on port, or the computer is on).

This also means if you plug your phone into a USB slot, and don't install any software, it should still charge... just as if you used that same exact cable with a wall AC/DC converter... just like the kind used for iPods and HTC phones, and Samsung phones, etc.

So, you need to explain yourself better... because if you took any standard USB cable, and cut the connections to pins 2 and 3, it becomes a USB cable that will only supply power.

Just so you know, I've built several USB LED desk lamps from scratch.... just because I had the stuff sitting around and the soldering iron was hot at the time.

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What do you mean by cut the connections to pin 2 and 3? Leave them open? I can charge my usb phone with the right driver, so I assume that with the right driver it does that (opens/cut connection of pin 2 and 3). So is there a generic driver that does that ? –  jacktrades Jul 12 '12 at 14:26
    
@jacktrades wow. All you picked up from all of that is "cut pin 2 and 3"? Seriously? None of the rest of it sank in? You didn't read the part saying that you need to explain yourself better? You didn't read the part saying that you don't need hardware drivers to provide power to a USB port? You missed those parts? –  Bon Gart Jul 12 '12 at 15:14
    
Sorry Bon. Thank you for your answer. I read all your answer. I'm looking for a way to charge the phone only by software. In other words: How to leave pin 2 and 3 open (while there is a 5 V difference in pin 1 and 4) with a windows driver? –  jacktrades Jul 12 '12 at 15:39
    
@jacktrades what exactly does "charge the phone only by software" mean? Software doesn't store or generate electricity. Do you mean you want some way to use a program to start and stop your phone from charging while it is connected to the computer? Your phone has a charging circuit built into it to stop charging the battery when it is full, so you don't need to control this yourself. Or do you want to be able to plug your phone into your computer and have it ONLY charge and nothing else... not connect as a storage device or anything else? –  Bon Gart Jul 12 '12 at 16:18
    
yes correct. "to be able to plug your phone into your computer and have it ONLY charge and nothing else" correct –  jacktrades Jul 12 '12 at 16:47

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