Electronics Forum | Wed Oct 03 09:56:51 EDT 2001 | Claude Tremblay
Hello everyone We have a QFP-308 (0.20" pitch)on a board and we have a lot of opens after reflow. We checked our profil by installing thermocouples on the pads of the component and everythings seems OK. We checked the coplanarity of the leads and it
Electronics Forum | Thu Sep 11 11:12:52 EDT 2008 | aj
Hi, I had similar problem a while back. Diagnosis was a combination of two things: 1 - Gold thickness was below spec. which gave us solderability problems. There should be other areas of the board that show signs of this. 2 - The devise in queast
Electronics Forum | Wed Sep 18 12:35:56 EDT 2002 | stepheno
Fourth - > back to design of PCB. Are there solder dams of > mask between the pads? If yes, that helps. If > not, pay close attention to stencil aperture > width and be sure that the aperture deposits less > paste by 1-2 mils per pad, centered o
Electronics Forum | Mon Jul 07 11:46:29 EDT 2008 | aj
Hi All, Can anyone advise the spec for land size of a lead 0.2mm in width? I am placing a TQFP128 0.4mm pitch, the leads seem to be wider than the actual pads they are been placed on? I am also experiencing poor wetting on this part , it has NiPdAU
Electronics Forum | Sat Dec 16 10:07:04 EST 2000 | Dave F
If I were you, I�d be concerned about waving your SO18 too. What is a SO18? Who makes that package? Regardless, it should be a can of corn, if you: * Orient it so that leads on opposite sides of the component see the wave at the same time. * Incre
Electronics Forum | Wed Apr 22 21:21:06 EDT 2015 | comatose
We see this from time to time. Usually, one of the leads of an electrolytic is attached to a ground plane, and the other to a trace. The ground plane acts as a big heat sink and reflows significantly later than the trace. If you have glue in your li
Electronics Forum | Thu Apr 12 22:54:06 EDT 2007 | mika
conductor on the narrowest place ~0.07mm we suggest them to go for a PCB solder pad down to 0.30mm. The Conductor width is: 0.2mm The current problem they are having now is that there will be a problem with 14V to narrow the conductor to the narrowe
Electronics Forum | Mon Jun 05 18:50:10 EDT 2017 | caurbach
Hi Zac, My 2 cents: We had similar problems on a board in the same situation (tin-lead HASL, very long leads, low pot height, high pump RPM). Trimming the leads shorter, moving the pot closer to the board, and dropping the pump speed down to sane
Electronics Forum | Thu Apr 09 09:25:04 EDT 1998 | Terry Burnette
| I am in urgent need of a pcb land patten (footprint)for this device. I have the component data sheet with with package dimensions from Motorola, but they do not include the recommended land pattern. I requested a patten over a week ago, but have
Electronics Forum | Fri Mar 07 21:02:21 EST 2003 | neil
When printing below .5mm pitch, the recommended stencil thickness is 5Thou, laser cut. Do not use any reduction and ensure wherever possible the pad to space ration is 1:1, the length of the pad is not as important as the gap between adjacent pads. T
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