Usb Port Broken

[rkrishnan2012]

Hi,
I got a free apple studio display monitor and I tried to convert it to work with hdmi port using the tutorial here:
http://lookanotherblog.com/?p=156
But somewhere, I think I connected a 25v line into the data+ or - and when I connect it to my win7, it says that the device is not working. Would you happen to know which part would be first to die when usb gets overpowered? (Ex., Capacitors, Resistors, Transistors...) Also, is there any way to check which part(s) would be fried?

I connect the hdmi cable and it seems that the monitor itself is fine but I need usb to actually control the power and backlight.

PS.
I also did the same thing to my laptop so is there any way to fix my laptop's usb port? It is not powered (with 5v) anymore on the right side.

Thanks,
Rohit

 

[popatim]

well 25v to the data line would most likely destroy the usb chip itself. Identifying it is a whole other problem

As for your laptops' USB, try connecting something like a backup drive that uses external power and not the 5v usb. If that works then you likely you blew a fuse or resistor and not damaged the chip. If that doesn't work then it looks like you blew the USB chip in that too.

And who know what else ...

 

[rkrishnan2012]

Well, the usb works without 5v so that might be a decent sign.

Also, is there a way to see if the chip is dead? I have isolated the chip in the board and I took a multimeter and it seems to give off the proper voltage between output and ground. Also, it is getting in the proper voltage between input and ground. The data+ and data- pins are stuck at a constant voltage of 3.84v.

Thanks!