isaacmc
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USB Output Voltage
does anyone know the standard output voltage for the USB port, and which wires inside the connector are the negative and positive, and maybe some links to some very basic usb guides, i was hoping to use the voltage for a small light for my keyboard, i like to do this simple diy stuff.
isaacmc,
The USB 1.0 Spec contains a cable length limit of 5 meters, a cable delay spec of 30ns and
a supply voltage minimum at any USB socket of 4.4 volts.
http://www.usb.org/developers/whitepapers/cablew~1.pdf
PL
The USB 1.0 Spec contains a cable length limit of 5 meters, a cable delay spec of 30ns and
a supply voltage minimum at any USB socket of 4.4 volts.
http://www.usb.org/developers/whitepapers/cablew~1.pdf
PL
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PeteLong,
Just one crucial bit of information missing from your post. Max current available on a port.
Max current is 500ma. If you are using an unpowered USB hub then the total current available will be 500ma split across the ports.
isaacmc,
I don't know what kind of light you are thinking of installing, but it will not be very bright.
500ma * 5v = 2.5 watts
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ThanQ
This solution has helped me out alot. I'm currently deployed in Iraq and was sent a christmas tree. The lights are powered by 2 C batteries. I used the information from this solution to help power my lights through a USB cable. I used the red cable for the Pos and the black cable for the Neg. Everything works great and the lights are actually bright instead of dim like when they had been powered by the batteries.
Brilliant! Hope you have a quiet tour, and you, and your friends all come back safe.
Pete Long (formerly CPL P A Long Royal Engineers)
Pete Long (formerly CPL P A Long Royal Engineers)
USB 1=4.4Volts minimum
PeteL