Electronics Forum | Wed Sep 07 00:28:04 EDT 2011 | woodsmt
I have identified a Board design issue and having trouble convincing others of my findings. I have a BGA (Sn63 balls, +1500 IO, 0.6mm ball, 1mm pitch, with heat spreader plate)that has a high incidence of solder shorting on the corners. The board i
Electronics Forum | Mon Oct 13 19:04:47 EDT 2003 | davef
Aperture size should vary with the component [pitch]. That size should be the same a the pad size. So, generally pinching is not required. Indium discusses BGA apertures on their site [ http://www.indium.com ]
Electronics Forum | Thu Jan 30 06:44:20 EST 2003 | Grant Petty
Hi, Great, thanks for the info! Regards, Grant Petty Blackmagic Design www.blackmagic-design.com
Electronics Forum | Sun Jan 26 21:09:32 EST 2003 | Grant Petty
Hi, Ok, thanks for the info, and I had not considered that factor. Is this an issue related to the reflow temperature change in the oven, or a temperature change in normal product use issue? I will check out the standard, and do you know where it's
Electronics Forum | Fri Jan 17 09:38:20 EST 2003 | Grant Petty
Hi, We have a BGA that uses .4mm diameter PCB pads on the BGA itself, however we have decided to use .5mm pads on the PCB, to help paste release from the stencil. Is this a bad thing, having different size pads on the PCB compared to the BGA itself
Electronics Forum | Sun Jan 19 10:25:54 EST 2003 | davef
You shouldn't freak. You want the pads on both sides of the BGA ball the same so that the torgue from changes in dimension due to different CTE [ie, interposer, solder, bare board, etc.] is balanced on the top and the bottom of the ball. So, the ma
Electronics Forum | Mon Jan 27 09:43:15 EST 2003 | davef
Sorry. I mistyped information on the guidelines. It should be: SM-785 - Guidelines For Accelerated Reliability Testing Of SM Solder Attachments Order SM-785 from: IPC 2215 Sanders Rd Northbrook, IL 60062-6135 847-509-9700 When you are ordering t
Electronics Forum | Fri Jan 17 15:36:23 EST 2003 | davef
How do 0.5 mm pads on the board help paste release from the stencil? Paste release from the stencil is a function of: * Paste * Printer operation * Stencil design You have no obligation to made your stencil apertures the same size as the pads on yo
Electronics Forum | Fri Jan 17 21:17:18 EST 2003 | Grant Petty
Hi, Our paste release problems have been solved, and we worked on the stencil, and things are working well now. However this board was designed before we knew what was going on, and we thought a little more size on the pads would be a big help. Is
Electronics Forum | Thu Jun 29 09:12:27 EDT 2000 | sree
What is the best aperture opening for micrBGA with 0.8 mm ball pitch and 16 mils ball diameter?The pad size on the PCB is 12 mils.
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