I have a relatively new (maybe a month or two old now) AR-750S that the USB port seems to have been damaged/died on. Opening up the case and inspecting the hardware I noticed that the chip marked “U29” looks to be exploded in the top-right corner so I’m guessing maybe the thing got hit by over voltage or something…
I’m not sure exactly what U29 is since the ID that should be printed on it is a blackened char lol Just wondering if anyone from GL can chime in to let me know if it’s OK to continue to use this guy with that chip dead/nuked, or if that does something else important beyond just regulating USB output voltage?
Router still boots and seems to run fine right now (just USB port is only 0.38V instead of 5V)…
Just to revive and old thread since it was started by me and is still related to the same original subject.
Since my original post I now have 3 AR-750S all with the same dead U29. Since AR-750S is offically EOL any chance GL can share a little more detail about what this chip is.
My guess, from probing around with a multimeter and looking at working units, is that it’s some kind of switch chip that gets controlled by GPIO 7 to turn power on and off to the USB port. Although it is a very small chip I’m willing to try replacing it myself (the AR-750S aren’t going to get any more dead if I screw up anyway lol), but I need to know what the thing actually is in order to get a replacement part.
Alternatively, if that information can’t be provided, does anyone know if there are some pads/pins I can just bridge or short out in order to permanently enable the USB power? It might be easier to simply heat gun the chip off and put a bridge wire in place if I can’t source a replacement.