Electronics Forum | Fri May 15 09:07:12 EDT 1998 | Earl Moon
| | I hear that there is a problem with using ceramic parts that are sizeable. Apparently, there is a mismatch in the Temperature Coefficient of Expansion between the FR4 and ceramic materials which causes the soldered erminations to weaken and event
Electronics Forum | Wed Nov 15 20:34:29 EST 2006 | davef
215. For more, look here: http://www.rohsusa.com/papers/PTV2.pdf
Electronics Forum | Fri Jul 16 13:33:31 EDT 1999 | Dale
We are converting from COB to SMT on a product line and want to optomize the PCB as far as Laminate, plating, passivation etc. This is a high temp application 150C. We are presently using BT Laminate but would like to get away from this. We are lo
Electronics Forum | Mon Jan 10 13:59:54 EST 2005 | mdemos1
Hi. I am looking for information on storing completed PCBAs in a warehouse environment. My current assemblies use standard FR4 material - 4 to 6 layers. Component types range from 0402s to fine pitch QFPs and micro-BGAs. If I were to store this i
Electronics Forum | Sat Nov 17 18:29:02 EST 2007 | bbarton
Let's face it guys...in most cases (stress the MOST!) a typical FR4 board will do the job. Few layers, low copper, not too densly populated etc...no worries. Use a reflow profile which avoids the 245-250C range, use a shorter TAL, Viola you have a go
Electronics Forum | Sat Oct 02 20:19:19 EDT 1999 | John Dwinell
| | I am currently in the middle of a company wide war and I'm looking for data (AMMO). Here are the problems: | | | | 1) I am looking for anyone who has done or seen any reports on Thermal Shock to smt parts and/or via holes caused by Soldering Ir
Electronics Forum | Wed Aug 18 15:56:20 EDT 1999 | david dougherty
Hadco offers a technology of building in a "buried" capacitance layer (& other embedded passives) in organic PWBs (FR4 for example). see http://www.hadco.com/prod03.htm and a design manual is posted here: http://www.hadco.com/pdfs/bcguide.pdf I am c
Electronics Forum | Fri Feb 28 01:10:32 EST 2003 | MA/NY DDave
Hi I don't know what FR4 you are using, so check it out to make sure 125 isn't too high. I have seen this done occassionally when the PCBs have bad moisture or other problemx where baking helps prior to assembly and solder, yet I haven't seen it do
Electronics Forum | Tue Jan 21 13:43:12 EST 2014 | rgduval
Jorge, Your description of the process sounds about right. A fixture to hold the flex cable taut (and in a repeatable location) that allows you to paste/place/reflow is essential. As for notes: Be hyper aware of moisture/humidity in regards to
Electronics Forum | Tue Aug 25 07:48:41 EDT 2015 | derrikf
Both pictures are from .031" FR4. According to my MOLE it's actually staying above the liquidus temperature for close to too long. Datasheet says 90 secs, I'm in the high 80's. Not ruling it out as a possible cause, I suppose the data I'm getting c
