Electronics Forum | Thu Apr 12 00:25:25 EDT 2007 | raychamp007
Thanks davef! We found some SOIC & QFP with all leads having toe down problem. The heel fillet unable extend to the mid point outside bend. Do you have solutions for the problem? I have a question: How about the normal gull wing lead which is flat &
Electronics Forum | Wed Nov 06 16:31:59 EST 2002 | slthomas
I would also consider paste control (don't take it personally...I always have to get after people about this one), time on the stencil, time between print and reflow, solderability of the component leads, paste volume (that one really got us once....
Electronics Forum | Wed Apr 11 20:49:39 EDT 2007 | raychamp007
3W. Figure 8-84 shown evidence of heel bend wetting(but no written criteria mention about the solder fillet must present at the heel bend). It is acceptable if the minimum D(3W/75%L)extend from toe which is no evidence of solder fillet at heel bend?
Electronics Forum | Thu Oct 26 12:36:02 EDT 2000 | Sal
Guys! witnessing a problem i've never seen before.Manufacturing a mixed technology with HASL finish, BGA,QFP's,fuses etc..etc. I've profiled the product, but what i'm witnessing is really weird. I've got a 0.020" QFP which is at the edge of the board
Electronics Forum | Tue May 18 16:22:43 EDT 1999 | Earl Moon
| | | Hi Guys, | | | | | | I am going to be graced with the good luck of processing microBGA's in the near future. A bit of a step forward from printing 20-mil pitch and wave soldering 0805's, wouldn't you say? | | | | | | So, any of you folks who
Electronics Forum | Mon Jul 01 11:29:02 EDT 2013 | hegemon
I am guessing a lead free process. From the pictures, I don't neccessarily see any issues, perhaps the leads have wicked up a little too much solder, making the joint look a little starved. But I think I see nice toe and side fillets. In the worst c
Electronics Forum | Mon Dec 22 19:43:43 EST 2003 | Dean
I have seen this affect on Immersion Tin and OSP. 70 to 90 % of the solder wicks to the lead and forms a "single" homogenous solder mass. This even though the pad was 100 % covered with paste... Evaluated different solder paste...did find variatio
Electronics Forum | Thu Mar 29 15:29:11 EST 2001 | johnw
measuring Paste volume or at least paste height is an essencial part of any SMT process. You've got to control those input's.... Paste volume determines how much solder is available for your joint so theres a direct to joint reliability / PCB reliabi
Electronics Forum | Mon Nov 22 11:16:04 EST 1999 | Boca
Chris, Some ramblings- Your choice depends on factors like which defects you're looking for, bugdet, quality inspection philosophy, high or low mix environment, sample sizes or 100%, and so on. Are you going to test 100% of the product coming off t
Electronics Forum | Mon Apr 19 17:33:17 EDT 1999 | Tuffty
25 PPM)! | | | | 1. Is there a better process to solder the leads of QFP's with lifted "minute" lifted leads still having a realiable solder joints? | | | | 2. Or has anybody tried modifying solder pads and use thicker solder paste deposit to compe
