Electronics Forum | Tue Mar 22 07:39:05 EST 2005 | davef
There is no standard. This is a relative test. If you wish to do tests of this kind, we suggest to pay attention to the following points: * Shear strength of soft solder depends on the deformation speed applied. The faster the material is deformed t
Electronics Forum | Tue Sep 09 15:22:39 EDT 2003 | gdstanton
Anyone have any experience with immersion white tin over copper plating? We are seeing opens develop under BGAs after we bake and conformal coat. And when we lift the parts the pads are 60% of the original size. Need some advice on possible causes
Electronics Forum | Wed Oct 21 10:18:00 EDT 2009 | stepheniii
Make sure the ground pad is reduced on the stencil and window paned. The solder on the thermal pad can lift the part up, especially if it traps gas. 360-380C does sound insane. I would believe a manufacturer saying 360-380F before I could believe
Electronics Forum | Thu Oct 29 20:19:43 EDT 2009 | 89jeong
Hi. We are doing Au bonding on Al bond pad not Au plated. If pull strength is less than 2.0g, i think that the ball or stich may be lifted from bond pad. And the value become lower after several reflow. I expect that the surface of bond pad may be c
Electronics Forum | Mon Oct 29 16:34:02 EST 2001 | patcope1
I have a custom connector that tends to lift during reflow. The PCB retention tabs and pins are lifting off of the pads on the board and the solder is forming underneath the pads, with no heel or toe filet. Is there anyone out there that can help if
Electronics Forum | Tue May 19 03:19:33 EDT 2009 | cunningham
Has anyone used a hot press to bond new pads to the boards if they have been lifted? we have one and have tried and carried out some DOE's on FR4 boards but when trying the same settings on Polyamide they basically fell of can anyone give any pointe
Electronics Forum | Wed Feb 10 10:12:35 EST 2016 | vaghelarajeshh
Thanks Mr. Davef, I had tried all possible factors to see good results. BUt I coudln't. 1. Baked Board 2. Board size is small. I used supporting pins so there is less chanches of bowing. 3. I tried to change the profile many times but result is n
Electronics Forum | Sun May 19 23:38:57 EDT 2013 | shrikant_borkar
We are EMS. Later revisions and Other models are get Modified. Now we have some remain Stock of Pcbs abd there end also. We have taken trial with Reduction in Apparatuses. But even small amount of solder paste at thermal Pad is causing QFN lift up.
Electronics Forum | Mon Aug 23 16:37:22 EDT 2004 | Terry
Three methods, all work, all require generous use of flux. 1.) Use a heated, electrical desoldering tool with flux. Just be sure that you select a forgiving desoldering tip with a rounded tip end to it so that you do not scratch the pad. Advantage:
Electronics Forum | Sat Jul 21 09:27:45 EDT 2001 | davef
No. There's nothing fancy. You need enough solder on the exposed pad for a good thermal connection, but not so much to lift the comonent off the TSSOP pads. We reduce the aperture for the pad, dunno 85%, with four windows [but it doesn't matter ho