Tool/software:
Hi
We experience PCBA yield problems with the CC3220MOD and need to modify the board.
The main problem is shorts between pads. We have identified production issues with the blank boards, where the solder mask opening is out of spec (it is too small). The opening is supposed to be 0.81mm but has been measured to be down to 0.71mm on the actual boards.
We thought fixing the solder mask size would be the right remedy. But now we see that the slua271c (QFN and SON PCB Attachment) application note contradicts the data sheet.
The data sheet suggests solder mask defined pads, the slua271c application note suggests non-solder mask defined pads. The CM also suggests non-solder mask defined pads.
So right now we are not sure if we should go ahead with the solder mask defined pads specified in the CC3220MOD datasheet, or change to non-solder mask defined pads as recommended in the slua271c application note and by the EMS.
Advice needed
/Morten
