Electronics Forum | Tue Dec 15 15:21:17 EST 2015 | davef
Peculiar that ENIG boards are corroded, not that it can't happen. * J-STD-002, Solderability Tests for Component Leads, Terminations, Lugs, Terminals and Wires * J-STD-003, Solderability Tests for Printed Boards The first person I'd talk with is my
Electronics Forum | Thu Jul 24 22:58:13 EDT 2008 | davef
At the 2004 IMAPS Nordic Conference, Claus W�rtz Nielsson from Nokia Mobile Phones published "The Evolution of Surface Finishes in Mobile Phone Applications" [www.imaps.org/adv_micro/papers/Nordic2004paper.pdf]. Some of the results were: * Corrosion
Electronics Forum | Fri Feb 17 09:08:22 EST 2017 | davef
An interesting paper on the topic is "The evolution of surface finishes in mobile phone applications" by Claus Würtz Nielsen at Nokia Mobile Phones R&D [http://www.cicmt.org/adv_micro/papers/Nordic2004paper.pdf] The paper reported corrosion problem
Electronics Forum | Mon Jul 26 09:19:57 EDT 2004 | davef
Both imm silver and ENIG provide flat surfaces that are better for fine pitch placement and reflow than HASL. We know of nothing that makes BGA locations different than other locations when using ENIG solderability protection. More broadly, the pri
Electronics Forum | Thu Aug 29 09:55:37 EDT 2002 | davef
Sounds like hyper-corrosion of nickel, commonly referred to as 'black pad', in ENIG solderability protected boards. Search the fine SMTnet Archives to get started. Additionally, the July - September 2002 'Journal Of Surface Mount Technolgy' has an
Electronics Forum | Tue Feb 21 01:32:49 EST 2017 | soldertraining
Looking for advice on soldering lead free paste to a board with very heavy gold plating, In my opinion, Gold contact surfaces are often used on circuit boards with membrane switches which is a choice of technology for industrial, commercial and consu
Electronics Forum | Wed Jun 14 20:49:32 EDT 2006 | davef
We too do not use ENIG. Too expensive and risky. Implementing a Simple Corrosion Test Method to Detect "Black Pad" Phenomenon in Electroless Nickel/Immersion Gold Plating ; BabHui Lee; Circuitree 11/1/03 http://www.circuitree.com/CDA/Archives/34f2b
Electronics Forum | Mon Apr 27 14:39:38 EDT 2015 | davef
Anirudh: When board fabs talk "surface finishing" they're talking about the solderability protection that you'd like on the solderable copper component mounting pads that you laid-out for each component: * Bare copper pads corrode very quickly * Corr
Electronics Forum | Sat Jul 28 08:37:52 EDT 2007 | davef
There is no good choice. Board Finishes: Industrial/Battelle Class 3 Environment [Reliability Knowledge Gaps: For use of Pb-free solders in High Reliability Applications, J Smetana, iNEMI Availability of SnPb-Compatible BGAs Workshop, March 1, 2007,
Electronics Forum | Wed Aug 24 16:30:11 EDT 2016 | shawn_halo_1
I have a 1oz Flex PCB (FPC) that has 2 0.4mm pitch connectors that need to be SMTd and 9 4.5x1.0mm pads that have conductive rubber contacts that are press fitted onto the FPC. The FPC has a one time bend radius of 15.5mm. Image is attached that show