Electronics Forum | Tue Aug 17 17:06:43 EDT 2004 | davef
First, we'd like to see your supplier's minimum Sn thickness to be increased to 10um. Look here for support of this position: http://www.psma.com/HTML/FILES/forums/leadfree/hp_ext_pos_sn_for_pbfree.pdf Second, increasing the thickness of tin: * Ra
Electronics Forum | Mon Feb 19 17:34:02 EST 2007 | GS
Thank You Pavel and Dave, Unfortunately I do not have IPC-4554. Anyway I 0.6-1.0umm is what I remember, and confirmed by reading also through leterature available on google. I was just going to understand if it possible to obtain more thickness
Electronics Forum | Fri Sep 25 16:47:57 EDT 2009 | esoderberg
0.5mm pitch QFP's are typically mixed with large components on all of my boards. I usually use a 6 mil stencil with a minimum aperture width of 10 mils. Normal aperture size is 10 x 50 which causes shorts about 20% of the time. A recent purchase of
Electronics Forum | Tue Feb 20 16:31:49 EST 2001 | davef
Let�s be basic. The two most common causes of BGA opens that we talk about here are: 1 Gold thickness and 2 Black pad. Given the thickness of gold that you talking about, it�s reasonable to consider thickness as the first alternative to investigat
Electronics Forum | Wed Sep 10 12:56:09 EDT 2003 | davef
Intermetallic compounds [IMC]: * Form during the alloying process of some metals. In soldering these are Sn, Ni, Ag, Cu, Au. * Do not accept solder. * Increase in depth in logarithmic proportion to both time and temperature. [So during the solder
Electronics Forum | Thu Feb 15 19:41:38 EST 2001 | davef
What do you mean by "But after performing temperature cycle test, the former aging rate (from the shear strength ) seems faster than the latter."? Comments are: I can't recall having heard the term "precipitation hardness" [not that that means anyt
Electronics Forum | Fri Jan 03 12:01:46 EST 2003 | jax
Alot of the companies out there use Standards developed internally, centered around there paste, equipment, and reflow processes. Normally you will see either 5mil or 6mil stencils used for everything in house with the exceptions of specific boards.(
Electronics Forum | Thu May 21 09:54:07 EDT 1998 | Justin Medernach
| I'm reviewing my board fab spec. It calls for a minimum SnPb thickness of 50 microinches on HASL PWB's. I've looked at other specs that call out anything from 30 to 80 microinches, and others that just say the copper pad must be covered and solde
Electronics Forum | Thu May 28 07:25:58 EDT 1998 | Earl Moon
| Hey yooze guys! | Enough of the jokes between you and Earl (GRIN), let's get back to the topic...well, okay... you can tell a few more...(but good ones, 'kay?) | Anyhoo...I'm not sure if ya'll are on the IPC Technet list or not, I've not seen any p
Electronics Forum | Thu May 28 05:43:33 EDT 1998 | Earl Moon
| Hey yooze guys! | Enough of the jokes between you and Earl (GRIN), let's get back to the topic...well, okay... you can tell a few more...(but good ones, 'kay?) | Anyhoo...I'm not sure if ya'll are on the IPC Technet list or not, I've not seen any p
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