Electronics Forum | Sun Jan 14 16:35:48 EST 2007 | Austin
I have several boards built at various CM's. We have prototype builds with some JTAG failures on BGA's (1-3 failures with qty 3, 1500 pin BGA's). CM's always claim reflow profiles look good. X-ray does not show bridges and they claim it looks good, b
Electronics Forum | Tue Jan 23 10:22:27 EST 2007 | Peter W.
Hello, maybe you are experiencing the so called "head in pillow" defect. It is especially critical for larger BGA. The defect comes from the deformation during reflow of the BGA, so that some of the balls are lifted and have no contact during liquid
Electronics Forum | Mon Jan 15 11:21:48 EST 2007 | davef
Contractor mantra: * Profile is good * Boards are bad On profiles, the key question is: where did you take the profile? We�d guess cracked connections are giving the intermittent test results when pressing on the components. You use acoustic micro
Electronics Forum | Wed Jan 24 11:24:07 EST 2007 | ruggi
I'm probably not telling you anything you don't already know, but a technique that's worked very well in the past for me is to methodically step through every part of the process and observe your boards being built, or take a scrap or simulated one a
Electronics Forum | Sun Jan 28 13:26:27 EST 2007 | Sweet Old Bob
Okay you CM haters I don't see anything about the design of the board, other than OSP which is strike one. What is the board size? What is the board thickness? Where is the BGA located on the board? What is your ball to pad ratio? What is your aspect
Electronics Forum | Tue Sep 13 09:12:12 EDT 2005 | stepheniii
I couldn't find any sanctioned procedure for dragging a pick across the leads to check for opens. I've never been a big fan of this anyways. Other than visually inspecting under a microscope and touching the leads that look suspect is there anything
Electronics Forum | Wed Jan 24 22:48:59 EST 2007 | frank63
Hello, we are facing some troubles with BGA opens in our production. PCB are both side popolated with BGA. BGA is array of 26*26, with some 6*6 center balls. PCB has 2 reflow processes, 4 pcs of BGA on each side. Now we are partly observing opens
Electronics Forum | Wed Feb 07 09:45:50 EST 2007 | billyd
...and, bake those parts. A lot of times, moisture will cause problems like you mentioned in the center of the part. (Old components will get this condition often)
Electronics Forum | Sun Feb 04 15:06:20 EST 2007 | Scotty
Profile should have a longer cool soak. Verify as was mentioned all pin/fixture support through out the entire process. Print, Place, pre reflow hand load, post reflow, carriers, ICT, Depanel and FCT. Conformal Coated or Potted? Mylars work well for
