Electronics Forum | Fri Jun 08 18:27:03 EDT 2007 | jmelson
This is probably an inner plated layer of the component that did not bond well. It may be a component that either has the wrong surface finish for lead-free or can't handle the temperatures. Many times I have seen a similar-looking layer when the l
Electronics Forum | Tue Aug 22 14:59:55 EDT 2000 | Mike Naddra
What does the reflow profile look like , the question I had was surrounding the higher reflow temperature and the max temperature that lowest thermal mass components will see. Some other questions that I had were surrounding the components , what of
Electronics Forum | Mon Jun 17 13:45:29 EDT 2002 | genny
When the pad comes off, is it leaving behind a "black" area? Your board may be suffering from black pad - a condition that occasionally affects ENIG finish boards. It is a process control issue with your board fabricator. The nickel is oxidising b
Electronics Forum | Wed Jan 09 15:24:49 EST 2002 | mregalia
Thanks Chris. As I was writing my last message our mailperson dropped off the latest issue of Circuit Assembly. It has an article on mixing SMT and COB on the same board. The author recommends as a compromise 10-20 micro inches of gold over 70-100 of
Electronics Forum | Wed Aug 19 08:00:55 EDT 1998 | Earl Moon
| Hi there, | I'm actually facing a lot of trouble with PCB's presenting up to 3mm of bow /twist at reception i.e. before assembly. The PCB size is 220 by 230mm. The boards are to be assembeled SMD double sides with 05.mm pitch on both sides. In orde
Electronics Forum | Wed Feb 25 01:24:34 EST 1998 | Steve Gregory
Dave, I confess I was a tad too general and a bit too extreme describing the way ALL solder joints look on palladium coated leads. I should been more specific about the "pillow-effect". I've seen it regularly with palladium coated leads on small SOT
Electronics Forum | Tue Jan 30 20:38:32 EST 2007 | davef
NASA Internal Advisory: NASA-Issued Return to Flight Wristbands Contaminated with Silicone [snip] 10. PROBLEM DESCRIPTION: Recently we have been made aware of a silicone problem associated with the "Return to Flight" wristbands. These wristbands are
Electronics Forum | Mon Nov 27 17:47:23 EST 2000 | Dave F
Gyver: Lemme take a wack [if you�ll excuse the expression, given direction of the later discussion] at your questions. Q1. Will the baking of BGA or PCB cause more oxidation before the SMT process? A1. It certainly will not cause less oxidation,
Electronics Forum | Fri Aug 17 11:55:31 EDT 2001 | davef
5uin. Your nickel thickness is fine. Although if you wanted to trade costs, consider giving-up nickel to 150uin thickness, while increasing the gold thickness. Gold over electroless nickel creates brittle joints because of phosphorous in the nicke
Electronics Forum | Tue Oct 24 22:36:29 EDT 2000 | DL
On the main page of Smtnet towards the end of the opening paragraph states the following...Your " research continues in determining the reliability of thick film hybrid microcircuits and similar technologies using low-temperature, co-fired ceramics.