Electronics Forum: reflow cold spots (Page 1 of 29)

White spots on PCB

Electronics Forum | Fri May 11 11:52:25 EDT 2001 | jagman

Does anyone know what would cause a PCB to develop white spots all over the board following parts placement and reflow? I need help!!

White spots on PCB

Electronics Forum | Mon May 14 19:16:49 EDT 2001 | jagman

Dave: Actually, I'm located in the South Bay (Santa Clara)! Good guess. Now, for more in-depth information: So far, the distribution has been limited to one board out of 10 assembled, so far from one lot. The components assembled are exclusively

White spots on PCB

Electronics Forum | Fri May 11 15:43:41 EDT 2001 | davef

More information would be helpful. For instance: * Talk about the distribution of the problem, including a single lot or from various lots and over components and component types on the board * Tell us about the board (ie, thickness, type, solder ma

White spots on PCB

Electronics Forum | Mon May 14 22:24:11 EDT 2001 | davef

The time over liquidous of the profile seems short. But then again, who knows? Based on what you told us, I'm guessing at a board fabrication problem, either measling or delamination. Probably the former, rather than the latter. [Now, we remember

facing cold joint problem

Electronics Forum | Mon Jan 19 14:54:38 EST 2004 | cyber_wolf

How did you come to the conclusion that you are having a cold joint problem. Just by appearance ? As Dave stated if you have any of the metals that he listed in the joints they will appear to be dull and grainy sometimes. But... Dave, I will have t

SMD ceramic capacitors dark spots

Electronics Forum | Mon Jul 23 11:02:56 EDT 2018 | mikedcmt

Thanks for your reply - parts in tape have similar markings - gets worse after reflow. ~20% have this issue. Units pass test no problem. Occurrence is random.

SMD ceramic capacitors dark spots

Electronics Forum | Mon Jul 23 10:56:38 EDT 2018 | dleeper

I've never seen this before and I would be suspicious. Have you tried to dust it off with a brush or Q-tip, it might just be some sort of process contamination. Have you looked at the reel to see if the parts are coming in with these spots from the

LQFP128 doesn't work when cold

Electronics Forum | Wed May 31 16:09:14 EDT 2006 | barryg

Did You verify operation of the oscillaators(resonaters) by heating and cooling and looking at the waveforms and frequencies when doing so. We have problems when they are not packed correcttly from vendors , and sometimes they can get crackes in them

cold joint on 1 lead of IC

Electronics Forum | Thu Feb 08 08:15:28 EST 2007 | tjcrume

I have received 10 customer returns for a cold solder joint on 1 lead of a 36 pin IC. Everytime it is on the #18 pin. The process is reflow and I can't figure out why the one leg is cold and the other legs look OK.

cold joint on 1 lead of IC

Electronics Forum | Mon Feb 12 10:02:18 EST 2007 | rgduval

A little late to the party here, sorry... Has the joint been verified as a cold solder joint? That is, visually confirmed that it looks like cold solder, and, perhaps, xrayed to confirm the solder status? X-raying may sound a bit extreme, but you'

  1 2 3 4 5 6 7 8 9 10 Next

reflow cold spots searches for Companies, Equipment, Machines, Suppliers & Information