MAX10 10M08SAE144I7G Not Working

[Altera_Forum]

Do wee need to solder the bottom copper pad to GND in order fpga to start working? 

We build 5 boards with proper oven soldering, copper pad soldered to GND. Only one board survived and working properly. If we heat up the fpga with heat gun they start working and as soon as next power recycle they don't work anymore. We prepared 3 more boards with hand soldering, without soldering the copper pad. None of them is working. Anybody had an idea to help us?

[Altera_Forum]

Hello, 

 it is said, into the pinout files (as a foot note) :   *"(2) The E144-pin package has an exposed ground pad at the bottom of the package. The exposed ground pad is used for electrical connectivity and not for thermal purposes. You must connect the exposed ground pad to the ground plane of the PCB."  I admit that there are better locations to write this "quite important" information (datasheet, handbook ?) !  Jerome.

[Altera_Forum]

--- Quote Start ---  Hello,  it is said, into the pinout files (as a foot note) :   *"(2) The E144-pin package has an exposed ground pad at the bottom of the package. The exposed ground pad is used for electrical connectivity and not for thermal purposes. You must connect the exposed ground pad to the ground plane of the PCB."  I admit that there are better locations to write this "quite important" information (datasheet, handbook ?) !  Jerome.  --- Quote End ---    Thank you jerome. This reply was important for us. Rasemeng

[Altera_Forum]

As said, exposed ground pad connection is mandatory. But I really wonder how you managed to make so many boards fail. E144 package is quite robust, I didn't yet see a single failure by inappropriate processing. Either you have exceeded the peak solder temperature considerably, there are discontinuities (e.g. by bad via plating) in your PCB or you missed to connect necessary MAX10 signals.