Electronics Forum | Fri Jun 01 22:09:03 EDT 2007 | mika
Hi Aj, What type of QFP are we talking about? We had in the past big problem with QFP-304 0.5mm pitch from ALTERA. Similar as you describe. Note. No problem with QFP-256 or QFP-196 0.5mm pitch, or anytying less than -304:s Can You be a little bit mo
Electronics Forum | Wed Sep 19 21:08:28 EDT 2007 | wailiang81
Those others parts also happend printed not accurate, but there is no solder problem. Only the QFP area looks bad condition.
Electronics Forum | Wed Apr 05 23:56:02 EDT 2000 | angela
Recently we have serious problem of our 0.5mm pitch QFP solder bridge. I check the viscosity of the Litton Kester paster. It's roumd about 700 is it too low. And do you have god solution about it? thanks alot
Electronics Forum | Tue Aug 30 12:06:41 EDT 2005 | MM
All of your response were similar to our investigation. Paste was sufficient, pcb's and parts came from several different lots run in at least 2 seperate ovens. Joints look good but the solder is soft?
Electronics Forum | Wed Oct 30 12:45:40 EST 2002 | davef
Dreamy, Pls snd pix
Electronics Forum | Wed Oct 30 23:19:28 EST 2002 | caldon
Is toe fillet still required?
Electronics Forum | Wed Sep 19 11:50:02 EDT 2007 | stepheniii
nevermind misread the post. But if the silkscreen is too thick, can you switch to another PCB manufacturer?
Electronics Forum | Wed Sep 19 21:10:16 EDT 2007 | wailiang81
Yupe, if condition keep worst, most probably will re-allocate the PCB manufacturer.
Electronics Forum | Wed Sep 19 21:13:24 EDT 2007 | wailiang81
By vision. Could you elaborate the meaning for "the advertised repeatability for your machine"?
Electronics Forum | Sat Oct 07 11:14:39 EDT 2000 | Aaron
1. It is hard to tell, but your PCB vendor should test the PCB. 2. I think the important thing is the width of the apertures. You should have it laser-cut, and control the width no more than 90% of half pitch. Good luck.
