Electronics Forum | Sat Nov 10 23:46:36 EST 2007 | mika
BTW, The surrounded QFN fine pitch terminals should have the normal aperture reduction of 7 % in case of RoHS Senju solder paste. This works for our Telecom customer. The vias in the ground pad will be somewhat filled with solder and makes it diffi
Electronics Forum | Mon Nov 12 09:22:41 EST 2007 | devajj
BTW, The surrounded QFN fine pitch terminals > should have the normal aperture reduction of 7 % > in case of RoHS Senju solder paste. This works > for our Telecom customer. > > The vias in the > ground pad will be somewhat filled with solder >
Electronics Forum | Mon Jan 12 08:59:57 EST 2004 | Paul F
I may have a similar problem at the moment with a QFP-68. Do the unsoldered leads leave a perfectly formed footprint in the reflowed solder? Do you usually find this issue occurring towards the corners of the QFP rather than in the middle of a row?
Electronics Forum | Thu Jan 15 15:08:43 EST 2004 | mrmaint
Are your qfp's being stored properly. I have seen this in the past and it turned out to be a moisture issue. We saw most of the problems on the corners. The component would swell during the reflow process thus lifting the corners. After baking the re
Electronics Forum | Wed Sep 05 08:10:45 EDT 2007 | davef
Questions are: * Do not judge the quality of a solder connection by the shineyness or color of the solder connection. Do you have smooth and unform flow, no pitting, and good wetting to the lead and the pad? * What is the temperature of the leads of
Electronics Forum | Sat Sep 15 01:42:36 EDT 2007 | mun4o
Hi, I attach the termocouples with high temperature solder wire, at the QFP pins.Other thermocople I attach at package with high temperature tape.
Electronics Forum | Fri Sep 14 14:20:23 EDT 2007 | sjcdcheu
What is the surface finished of your board and what is the peak temp at your solder joint?
Electronics Forum | Wed Jan 14 10:07:38 EST 2004 | Patrick
More on QFP soldering issue as per Paul f original e-mail. 1. Problems occured on different PCB's, on different lines using different equipment 2. Flux residue is common in the dimple on the solder. 3. The fault occurred using both "Kester 265" & "Al
Electronics Forum | Mon Sep 10 18:04:28 EDT 2007 | slthomas
How are you attaching your thermocouples to measure the temperature of the lead/pad connection?
Electronics Forum | Tue Sep 25 14:43:28 EDT 2007 | mun4o
Hi, we change Kester with Interflux and all it is OK.The problem was paste Regards