Track_Shovel
Vinny_93What did dude think was coming out of the VGA port? Tiny photographs? It’s all electricity through wires, of course it’ll send some electricity into a phone
Yeah but is the voltage correct? It should be 5V to charge a phone over USB, is that part of the VGA spec?
With USB power delivery, you can get 9V, 12V or higher over USB. Usually the device requests higher voltage from a PD charger, but it’s not impossible for a modern device to be able to cope with just having 12V shoved into it.
The USB device would have been made wrong if it just shoved 12V down the power lines without negotiating it.
That’s probably only true for USB power supplies - a USB adapter isn’t set up to do anything with voltage and probably just passes the positive and negative pins through.
The VGA adapter feeding power back through USB in the first place, yeah, that’s not supposed to happen.
Yeah I don’t think there’s a 5V pin for VGA.
I think if we had the scenario where we had a higher voltage than needed, we could have a toasty voltage regulator making something happen, but going the other way would need boost circuitry unlikely to exist in these parts, in my understanding
AniviaDoesn’t matter. The VGA to HDMI adapter is active, not passive, so it matters if HDMI has a 5v rail, not VGA
If, hypothetically, VGA didn’t have a 5v rail then how would power get from the monitor to the HDMI adapter. It would absolutely have to be a part of the spec.
knight_alvaIf the vga/hdmi adapter is active then this abomination could actually pass display information provided you had a micro-usb device that supported display out over usb (idk if there is such a thing and if so it probably doesn’t work all that well but still)
SundrayI don’t know shit about cables but it’s plugged into a monitor. My intuition is that a monitor shouldn’t be pushing power out through a video input port.
Signals aren’t magic, they consist of electrical power. You can get at least a little bit of power from anything that isn’t an optical port.
Technically, even an optical port delivers power. Visible light is just a particular form of electrical power that transmits a bit differently (you might need a different detector to make use of the energy from a beam of light), but it also has an intensity, voltage and resistance in the medium of propagation.
DisplayPort has a +3.3V 500mA pin specifically for pushing power. In theory, great for powering an active adapter. In practice, has killed motherboards because Dell can’t design a computer for shit.
VindictiveJudgeThe monitor has to send some data to the computer to tell it what screen resolutions it accepts. VGA, HDMI, and DisplayPort will all do that for sure. Less certain about component, composite, and S-Video.
Of course electricity comes out of a VGA port, but it's only a signal, I wouldn't assume that it's anywhere near enough to charge a phone.
Pin #9 of the VGA spec is 5v, though it seems unusual that a monitor would provide power on that pin
potoooooooo ✅️Thank you, I call bullshit.
Maybe somewhere in the chain, the 5V from pin 9 is being converted to 5V shared across power and the video signal. So even if this chain worked in carrying a video signal it could be very weak or distorted.
Purely a guess though.
The VGA port on a monitor is an input.