3 months ago I setup my new RB750 Router and today i encountered a hardware failure on him. After i noticed that network is not working and i can't connect to the router with Winbox the next step was to verify the router himself. The router was OFF, like there is no power supply on him. I unplug the Power adapter and plug in again but only a very short blink off all leds and then all dark again. Tried couple of times to unplug and plug again but the result was the same. I checked the Power supply with multimeter but it looks ok, 12V output. I took the Routerboard PCB out of the case and tried again the PowerUp procedure. After a couple tries i noticed a very very thin line of smoke. It looks like was coming from U2. Looking carefully in that area i noticed a 3V3 Test point but testing with multimeter there are no 3V3 present on the board. The U2 gets input of 12V on pin2 but there is no 3V3 output on the board.
Can anybody help me to fix this problem? It's clearly a hardware fault but it strange to me to occur on a brand new RB750 and powered through UPS. Is maybe this a common fault to this model?
I made a search on the internet and noticed that there are many PCB versions of RB750 with different component casing and placement on the PCB. I attach the picture of my router PCB version (sorry for the quality of the photo):