Electronics Forum | Thu May 31 10:21:16 EDT 2001 | davef
On "Flip Chip/uBGA Under-fill Visual Standards" � The third "Satisfactory" [The under-fill if by design should be visible � ], here the notation "if by design" is unclear. Does "according to product documentation" get to the point? The first "Acc
Electronics Forum | Fri Jun 01 12:23:22 EDT 2001 | medernach
I've had good and bad experiences with OSP's. First of all, ask yourself, "Why use an OSP?" If you don't need it, don't use it. Solderability is dependent upon the number of thermal passes (the fewer, the better), the thickness of the coating, the
Electronics Forum | Mon Jun 11 21:56:41 EDT 2001 | davef
Continuing, I�ve optioned about the uselessness of shear testing of solder connections on this forum previously. So, the points that you make about the elusiveness of developing a standard for measuring solder connection strength is well taken. I�l
Electronics Forum | Mon Jun 11 22:06:00 EDT 2001 | davef
The issue is not the cleanliness of your in-bound water. The issue is the cleanliness of the board your customer receives. Look at J-STD-001C, Para 8, "Cleanliness Requirements". The end product cleanliness is the end result of your: * In-bound
Electronics Forum | Tue Jun 12 18:06:17 EDT 2001 | davef
The criterion you use will depend on the test method you select. For minimum requirements, look at J-STD-001C, Para 8, "Cleanliness Requirements". I figure that you�d measure the residues on a lot of your current product, measure the res on a lot o
Electronics Forum | Fri Jun 15 14:05:20 EDT 2001 | CPI
In response No that�s not all you need to think about, but lets look at each and then talk of others. a)The condition of the solderable surface on boards (and components) degrades over time or can be supplied in poor condition (to thin or thick HASL
Electronics Forum | Tue Jun 26 19:51:31 EDT 2001 | davef
Rosin. A hard, natural resin, consisting of abietic acid [and pimaric acids in Europe] and their isomers, some fatty acids, and terepene hydrocarbons. Rosin is extracted from pine tree stumps. It�s an organic material distilled from oleoresin in p
Electronics Forum | Mon Jun 25 20:37:14 EDT 2001 | davef
You are 100% correctamundo that the pad on PCB should be the same as the pad on the BGA interposer, but let�s not expend that thinking to the aperture of your solder paste stencil, right away. Generally, paste on large pitch BGA is often 1:1, but as
Electronics Forum | Thu Jun 28 08:14:11 EDT 2001 | Stefan Witte
I visit customers on a contract base to get the machines in a status, that an operator can take over. These customers are usually small shops, who can not effort an engineer to set up the machines. I am not afraid of my job, if it does not require a
Electronics Forum | Sat Jun 30 11:03:29 EDT 2001 | davef
Nice to have you back on SMTnet. Some of the newer folk have missed-out on the solid contributions you�ve made to the Forum. The chicken wire cleaning basket was a classic!!! [It�s a shame that the folk at SMTnet can�t recover those files.] We bu
