I'm searching for any kind of information about the i.MX28 MAPBGA package. Datasheet says nothing about Paste Mask and Solder Mask expansion. As it is the first time I'm going to work with BGA I would like to pay special attention to every detail at the design stage.
Thank you very much for the help. I use Altium and it has an importer of Allegro files but don't work if Allegro is not already installed in the computer and I can't take a look to the gerber files coming with the EVK. So very useful your comments!
as land pattern I've used the same value used in the EVK: 12mil. But I suspect that 13mil will be also appropiate.
With 4mil width/space for tracks and 8mil/16mil pad/hole for vias: the minimum reliable track/space for mask has been 0.08mm, in my case. DON'T FORGET TO COMPLETELY TENT ALL THE VIAS UNDER THE BGA COMPONENTS. Regarding to the solder mask: I didn't put anything and my assembler did it for me.
My custom board works right. On any case I've planned to buy some IPC standards in order to be sure of what I'm doing on next designs.
Hope be helpful.