Electronics Forum | Thu Aug 03 11:32:44 EDT 2000 | bzark
Any opinion on what size aperture and stencil thickness is most optimum for Land Grid Array 1.27mm pitch with .6mm pad using SN/AG NC solder paste?
Electronics Forum | Tue May 22 17:24:12 EDT 2001 | davef
What is your thinking on the issues surrounding design and manufacture with leadless leadframe [eg, land grid array, micropak] components beyond those in http://www.national.com/ads-cgi/viewer.pl/an/AN/AN-1187.pdf? The curve ball that we just looked
Electronics Forum | Wed Apr 09 09:44:12 EDT 2003 | iman
yes, we r profiling direct thermocouple attachment to the LGA pads. based on direct experience of yourself or others, what paste (brand/type3?/type4?/alloy?/flux%?) gives the optimal repeatable characteristic-patterns to minimize this defect?
Electronics Forum | Fri Feb 25 12:04:21 EST 2005 | davef
Land grid devices [ie, BCC�, LGA, QFN, MicroLeadFrame�, etc] are essentially BGA devices with the balls removed and with no solder on the pads. Search the fine SMTnet Archives for background discussion.
Electronics Forum | Sat Mar 24 19:49:29 EDT 2007 | mika
Aj, Many Thanks and I will of course share our experience about this. /Mika
Electronics Forum | Fri Apr 06 08:17:25 EDT 2007 | davef
Mika: What are the size and shape of the pads on: * Board * Interposer of component Are either of these solder mask defined?
Electronics Forum | Thu Mar 29 21:47:41 EDT 2007 | davef
PCB land to part land ratio - 1:1 Stencil aperture size - 1:1 with PCB land Stencil aperture shape - same as PCB land
Electronics Forum | Fri Mar 30 23:07:13 EDT 2007 | mika
And how about the queston: http://www.smtnet.com/Forums/index.cfm?fuseaction=view_thread&CFApp=1&Thread_ID=11592&mc=7 We face a big problem with this matter right know. /
Electronics Forum | Tue Mar 04 16:09:05 EST 2008 | dphilbrick
Everything you wanted to know (and possibly didn't want to know) http://www.freescale.com/files/32bit/doc/package_info/AN2920.pdf
Electronics Forum | Tue Mar 04 17:06:31 EST 2008 | realchunks
Depends on your board? What finish? Solder mask between all pads? What pitch is the part? Will it machine placed? Don't forget proper profiling as well. 1:1 with machine placement should yield no issues.
