Electronics Forum | Fri Apr 17 14:08:44 EDT 1998 | Earl Moon
| Currently I am in the buisness of soldering bare die to the top surface of a copper heat sink. Is any one else | have some exprience in this process that can help. We heat a copper slug through a contolled atmosphere, place a preform then a bare
Electronics Forum | Sat Sep 27 10:40:24 EDT 2008 | hussman
Hello all, Just had a problem where the solder paste does not want to stick to the pad, thru the stencil. We have run this board for years with no problem, and this new lot of boards is giving us problems. I know it's a board problem because they
Electronics Forum | Wed May 27 16:02:32 EDT 1998 | Chrys
| We recently made the switch to no-clean and the wurface mount is turning out beautifully. However, the wave solder process continues to put up a fight; we are getting a white residue on the surface of the PCB. The residue is not localized to
Electronics Forum | Fri Sep 11 15:27:50 EDT 2015 | u4bga
Hi! We're noticing white spots on 2 PCBAs after the selective soldering & DI Wash processes. ----Facts---- 1) The marking is on all boards, irrespective of date code 2) It only happens on leads that have been selective soldered 3) The pattern of w
Electronics Forum | Wed Dec 08 10:10:41 EST 1999 | John Thorup
Hi Dave I think you just provided the key to understanding the problem. By your description you are talking about a CBGA (ceramic). These typically have balls composed of 10/90 Sn/Pb which melts at a higher temperature than the 62/36/2 Sn/Pb/Ag (or
Electronics Forum | Wed Nov 06 10:31:30 EST 2002 | davef
First, from what you say, it's unclear that there is a "solderability" issue with your connectors. Different appearance of the soldered connection from one side of the connector to the other is what we're talking about [I think]. But it is curious.
Electronics Forum | Thu Dec 09 09:51:34 EST 2004 | russ
One of the things that I have found is the "benchtop/lab" type waves (Low cost) do not perform very well except on the simplest of products, they are lacking critical design elements such as adequate preheat length, laminar flow nozzle design, etc.
Electronics Forum | Mon Aug 18 11:20:08 EDT 2008 | pjc
Stencil apertures are cut to deposit solderpaste onto the annular ring, provided its wide enough. Then you can place a solder preform if needed to ensure there is enough solder to fill the barrel. Here is some information on solder preforms: http://
Electronics Forum | Wed Jan 21 03:44:04 EST 1998 | Igmar
| We are currently investigating alternatives to HASL for circuit boards with 20 mil pitch smt pads and below. If you have experience with this product or simular immersion tin products with respect to manufacturing or assembly I am very interested
Electronics Forum | Tue Sep 09 07:03:56 EDT 2008 | mun4o
Hi All, we poduce diferent kind of Keyboards, and use a lot of SMT LEDs.When I looking for reflow soldering Conditions i n the Data Sheets, usually I find "IR-reflow" Soldering profile.Our Reflow owen have onli conventional heating.Is that problem?
