Hi @Genoil
In general I have to agree with Daniel’s analysis, I to would guess you have had an ElectroStatic Discharge (ESD) event which has taken out the WCD. I can’t stress enough how sensitive modern electronics are to ESD if you are not working at a properly grounded workstation and wearing an ESD smock, and wriststrap, then any handling of an open board brings with it a likelihood of generating an ESD event that takes out one of those tiny transistors on one of the chips. Even with a grounded work station, smock and wrist-strap I would also recommend an air ionizer blowing ionized air over the work surface.
I you (like most people) are not willing to go to the pain of properly handling your electronics, then you take a risk every time you move your hand near the board (you don’t even need to physically touch the board to generate enough potential to take out a device). Since these boards are generally inexpensive, we usually just get another board out of the box and move on when this happens.
When boards are closed up into boxes (like a cell phone or DVR) all of the external ports have special ESD protection devices, and the case protects the points that don’t have protection. if you look at the schematics for the 410c you will see ESD diodes near things like the USB ports. These ‘usually’ protect the ports against ESD, but even then a sufficiently large discharge will take them out. In a cell phone design we even put ESD protection devices at the connections to the speakers, and microphones since they are open to ESD. Unfortunately ESD diodes are expensive and take up space so we can’t put them everywhere on the board.
Here is a very quick overview of what you need to do https://www.esda.org/about-esd/esd-fundamentals/part-3-basic-esd-control-procedures-and-materials/ if you want to be sure your board doesn’t suffer and ESD event, otherwise just have a spare.
-Lawrence-
No longer a Qualcomm employee.
Still looking for work
