Electronics Forum | Wed Jun 16 14:14:07 EDT 1999 | Dave F
| Hello, | I am looking for the surface resistivity and volume resistivity of standard fr4 as a function of temperature and /or humidity . can any one help? | Frank: Sorry I'm so late getting back to you. 1 Use either ASTM D5109-94 or IPC-TM-6
Electronics Forum | Fri Jun 18 03:31:38 EDT 1999 | Frank
| | Hello, | | I am looking for the surface resistivity and volume resistivity of standard fr4 as a function of temperature and /or humidity . can any one help? | | | | Frank: Sorry I'm so late getting back to you. | | 1 Use either ASTM D5109-
Electronics Forum | Tue Apr 18 07:28:32 EDT 2006 | JH
Mark, I am having difficulty picturing exactly what you are doing, but I hope this helps. We occasionally use jigs through SMT, usually because the board is too small/thin to fit the smallest rail width. In such situations, we normally make the jig
Electronics Forum | Wed Jun 22 02:30:33 EDT 2011 | boardhouse
if its a RoHs Assembly they should be using an FR4 material designed with higher TD to handle higher Assembly temps. 370HR,IT158, IT180, 4000-29 just to name a few that would be suitable. Standard FR4 material is not designed to handle the higher as
Electronics Forum | Tue Feb 01 10:49:39 EST 2000 | AF Ng
Could someone help to let me know which Standards ( IPC or others) which spell the number of thermal excursion that FR4 boards is allowed to exposed to ? Thank you
Electronics Forum | Tue May 24 03:53:52 EDT 2005 | Rob
Hi Doug, Can they be mounted on standard FR4 PCBs & reflowed at Lead Free temperatures? Cheers, Rob.
Electronics Forum | Tue Oct 11 17:27:49 EDT 2005 | artekeng
Depending on the metal and bond to FR4 you may be able to get a better profile if you use conductive heating.(vs standard convection reflow)
Electronics Forum | Wed May 03 16:37:10 EDT 2017 | charliedci
I don't believe there should be any issues with the HASL finish. The issue is how long on the shelf and is a bake out required to remove moisture from PCB, as in any FR4 PCB's that may have had time to absorb moisture.
Electronics Forum | Mon Nov 27 17:44:10 EST 2000 | Dave F
Gawd. Sure FR-4 will meet those conditions. Tg [check the fine SMTnet Archives for discussion on Tg] of FR-4 is 130�F or so. Consider: * Is the delT between Tg and the upper operating [or storage] temperature acceptable for your application? * D
Electronics Forum | Mon Oct 16 11:12:42 EDT 2000 | NLykus
CEM 1 is a laminate base board material. The other boards in the experiment were manufactured using FR4 as the base board material. What I'm leaning towards is that the glass transition temperature "Tg". What do you think? Topside temperatures in
