Electronics Forum | Mon Mar 13 13:01:08 EDT 2017 | emeto
Very interesting, how you can answer that with that many details that you gave us. Here are some preliminary questions, before anybody can give you any answer: Pb or Pb-free? 3mil stencil or 8mil stencil? How many shifts? Quantity will depend also o
Electronics Forum | Mon Mar 13 17:25:54 EDT 2017 | parto
Dear Evtimov, Hi, many thanks for your decent answer. I utterly agree with you that if I would like to have an accurate answer I had to give you more details as you mentioned in your reply.However, I thought that under certain circumstances any prod
Electronics Forum | Wed Mar 15 04:36:16 EDT 2017 | Rob
@ Sr.Tech, Any voiding means that the part of the package under the void is not forming a solid thermal interface with the PCB, therefore it's heatsinking capability is reduced. With the drive for smaller packages with higher power handling capabil
Electronics Forum | Wed Mar 15 08:47:50 EDT 2017 | emeto
From what I know, you should follow IPC standard for the class assembly that you are building. From your post somebody mentioned something somewhere - doesn't make it official information. I would not be worried about having voids, but what is their
Electronics Forum | Wed Mar 15 09:53:58 EDT 2017 | rob
Hi Etimov, Understood that to us assembling parts that IPC is king, however it isn't neccesarily the bible for design engineers. We've had customers demand almost zero voiding, or had to use conductive epoxy to avoid it. For some of us solder joi
Electronics Forum | Wed Mar 15 10:21:08 EDT 2017 | pzappella
Hello Rob, I totally agree with you. Is this a real problem that is being shoved under the rug or just whatever voiding we get from a belt furnace is good enough. I think vacuum reflow can do much better but is a batch approach and not contin
Electronics Forum | Thu Mar 16 03:45:51 EDT 2017 | rob
It's the same thermal issue whether it's a die or package. It's different if it is just a signal trace, but if it's a heatsink pad (LED, FET, Motor driver, PSU IC etc). I think the voiding issue boils down to what the part is actually doing. The or
Electronics Forum | Thu Mar 16 19:12:22 EDT 2017 | pzappella
Hi Rob, Thanks for the LED paper. I like the void area equations but I am puzzled, the paper did not say if the solder was a solder paste that would generate a lot of voids, or a fluxless preform or sinter material. The measured voiding level
Electronics Forum | Tue Mar 28 19:43:49 EDT 2017 | aemery
Simon, Trying to dust off my 400 knowledge here, I can picture the 500 and 1500 better in my head. I think the 400 also has a Z axis amplifier box in the back of the machine. Remove the rear lower door and pull out the big square vacuum box. If it
Electronics Forum | Thu Mar 16 22:19:38 EDT 2017 | deanm
First, reflow does not reset the clock for MSL exposure. The best solution is to run the second side before the exposure time expires. I am curious to know why they must sit for 40 hours. If that cannot be done, then store the assemblies in a dry c
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