Electronics Forum | Fri Apr 29 14:16:16 EDT 2011 | ppcbs
Below is the long explanation. This defect is most commonly found with BGA components, but can arrise with all components. I see it happening more now with lead free boards that are being assembled with a no clean flux. Best short term remedy is t
Electronics Forum | Thu Aug 28 16:13:06 EDT 2003 | Dan Gosselin
Thanks everyone for your help. I have since found a good article I am downloading of of the SMTA website. Dan Title : EFFECT OF SURFACE TENSION OF SOLDER ON UNDERSIDE DEVICE SUPPORT DURING REFLOW OF A PCBA Author : Mulugeta Abtew Author Company
Electronics Forum | Wed Aug 10 10:41:23 EDT 2005 | patrickbruneel
Bob, Great theory if you're selling SN100C, but I have to disagree that an alloy being 4�C off eutectic will cause cracks. When a solder joint exits the solder wave, there is an immediate drop in temperature of 100�C. so being off 4�C is irrelevant.
Electronics Forum | Thu May 26 08:52:42 EDT 2011 | davef
Phil Zarrow wrote a useful paper that could help in evaluating paste. Here read it ... Evaluating Solder Paste � Not An Option Contributed by Phil Zarrow of ITM an Independent SMT consulting firm With soldering being the dominant source of assembly
Electronics Forum | Wed May 08 23:18:58 EDT 2002 | ianchan
Hi mates, have this SMT production issue : A) We have a leadless-chip-carrier(LCC) IC package that is classified under the Land-Grid-Array(LGA) package family. B) The LCC is 4mm x 4mm, and has 28 tin plated pads located beneath the outside perimet
Electronics Forum | Mon May 10 08:00:14 EDT 1999 | Timothy O'Neill
| | | | I am about to embark on an effort to evaluate 3 different solder material suppliers and their recommended materials for our assembly process, in an effort to find the best supplier/material. We do mixed technology, with NOCLEAN chemistry so
Electronics Forum | Tue May 04 14:42:58 EDT 1999 | Chrys Shea
| | I am about to embark on an effort to evaluate 3 different solder material suppliers and their recommended materials for our assembly process, in an effort to find the best supplier/material. We do mixed technology, with NOCLEAN chemistry so I wi
Electronics Forum | Mon May 10 07:53:48 EDT 1999 | Timothy O'Neill
| | | I am about to embark on an effort to evaluate 3 different solder material suppliers and their recommended materials for our assembly process, in an effort to find the best supplier/material. We do mixed technology, with NOCLEAN chemistry so I
Electronics Forum | Fri Jul 08 16:35:04 EDT 2005 | Jason Fullerton
"Whether or not you need a toe fillet depends on your application. We have high reliability products where we can't use a QFN over a certain size, regardless of toe fillet. We have other applications where we meet the thermal cycle requirements for a
Electronics Forum | Wed Jul 06 14:36:05 EDT 2005 | Bob R.
The only way we can consistently get a toe fillet is to use a paste with an extremely active flux. We allow that paste on certain products, but discourage it's use because it's on the hairy edge of not meeting our lower limit in surface insulation r
