Electronics Forum | Wed Feb 07 18:40:39 EST 2007 | bill
What is an acceptable mismatch for smt components and pcb. We are having cracked solder joints from fatigue after repeated thermal cycling 25 deg. c to 125 deg.c.
Electronics Forum | Thu Oct 24 03:03:13 EDT 2002 | harriss
Hi: The component height will increase on the PCB after reflow soldering. But i don't know the accurate data of the increased height. Who can help me to get it? The stencil thickness is 5 mil we used. Thanks Harriss
Electronics Forum | Thu Oct 24 13:32:03 EDT 2002 | russ
There are many factors that will affect post soldering height. Lead shape/type, pad geometry, fillet formation, etc... You will need to measure each type of component before and after reflow. Russ
Electronics Forum | Thu May 13 09:47:32 EDT 2004 | Lubo
We are looking for a inspection system to check the positioning of a component over a PCB. We need it positioned both in X Y directions and height above PCB (it is a TH component) to be within certain limits. PLS advise can this be achived by AOI. Wh
Electronics Forum | Thu May 13 17:07:44 EDT 2004 | Longhua
Try TESTRONICS 505 series. Ask for literature on this subject. They are a very responsive company.
Electronics Forum | Tue Dec 28 12:34:03 EST 1999 | Justin Medernach
Jim, I wouldn't sweat a TCE mismatch between Ceramic chip components and FR4. No need to worry. 99.5% of consumer product out there utilizes this exact technology with no threat of failure due to CTE mismatch. The terminices of the components occu
Electronics Forum | Wed Dec 29 15:42:34 EST 1999 | Mike Naddra
Justin, I would be currious as to your customers application, and if the temperature delta and rate are great enough to cause solder joint failures as a function of mismatched Tce then you may want to consider that even if you are able to identify
Electronics Forum | Wed Mar 30 08:06:17 EST 2005 | davef
Considerations are: * If the nonwetting is component lot specific, the could be solderability issues with that lot. * If the nonwetting is is a broader based component issue, the solderability protection on the component may require a different reflo
Electronics Forum | Wed Mar 30 01:01:10 EST 2005 | vicknesh28
All, Has there been any finding from the component point of view in terms of non wets after reflow and if yes, can anyone share what was improved on the component to reduce the non wet defective levels. What would be the contribution from the compon
Electronics Forum | Sat Apr 25 19:40:01 EDT 1998 | Stan Traxler
| We have to mount our SMD devices 0.1 to 0.4 mm off the pcb | PCb substrate to compensate for thermal stressing in a | Space enviroment. Has any one any ideas or contacts for | dissolvable pads. this only applies to leadless components We have appl
