Electronics Forum | Mon Aug 06 07:15:14 EDT 2012 | reypal
Hi to everyone in this forum. I came across this problem recently. Im not sure how it started and its rootcause. The chip resistor termination has been peeled off. Thanks in advance for all your advise.
Electronics Forum | Mon Aug 06 16:47:41 EDT 2012 | duchoang
Can you give more info: - Hand-soldered? Placed by Pick&Place machine? What kind of SMT machine? - Oven re-flowed? Temperature? - Any physical impact?
Electronics Forum | Tue Aug 07 01:19:49 EDT 2012 | reypal
Thanks DucHoang, More input: 1. Tin/Lead s.paste on Pbfree component 2. Machine pick and place 3. Reflowed@ 210-230C peak @ around 15sec. 4. Boards are subjected to washing process 5. This issue can be seen after washing process. Do you think it
Electronics Forum | Thu Aug 21 08:15:07 EDT 2008 | naynayno
Thanks Dave, I will be sticking with Manufacturing Engineering. These are good guidelines but what is standard clearance for various packages? This is a dimension we usually seek by eye, whether we will have a problem or not. We use straight DI -
Electronics Forum | Wed Aug 20 17:05:42 EDT 2008 | naynayno
We have experienced contamination under flat chip arrays. The lab report is still open but it appears to be dendrite growth. We have been trouble-shooting our process and cleaning equipment. My question is are there any specific design or best p
Electronics Forum | Thu Aug 21 08:33:09 EDT 2008 | davef
There is no standard as such. It's easy to see why. It's too complicated and has such a small payoff. Standoff is comprised of: * Package height * Solder thickness between the pad and the component lead * Delta of pad thickness and solder mask For p
Electronics Forum | Wed Aug 20 20:10:30 EDT 2008 | davef
Naw, accounting is boring. Standoff could be an issue. Coupla things: * Above 30 thou, just about any cleaning process, more sophisticated than a garden hose, will produce acceptable results * Below 10 thou, can be cleaned with best efforts, but not
Electronics Forum | Thu Apr 27 02:39:50 EDT 2017 | ajaytyagi
Thanks for sharing your experience. I have similar view too.
Electronics Forum | Wed Apr 26 06:09:12 EDT 2017 | ajaytyagi
Hi, Pl let me know about opinion/experience whether thick film chip SMD resistor which is MSL-1 Required to bake before being usedon SMT line. I want to use SMD resistance spool which is around 2 yeasr old kept at 25 deg room temperature at around 4
Electronics Forum | Wed Apr 26 08:13:47 EDT 2017 | spoiltforchoice
MSL 1 is unlimited factory floor time before reflow. I have spools that are 10+ years old and haven't encountered any issues using those parts. It goes without saying those parts are not exactly used in volume so its not a massive sample but that is
