Electronics Forum | Tue Apr 09 07:41:08 EDT 2002 | johnw
Craig, it depend's n what you want to look at. In term's of te gran structure of the solder jont that's formed when the joint is cooling so you'd want to monitor the temperature drop from the peak or say 215dg C for ref down to probably about 150 an
Electronics Forum | Thu Apr 11 19:06:59 EDT 2002 | tmarc
We are using 1mm pitch BGAs with a great quantity of via(s) under the component. Very shortly we will be placing CSPs with .65mm pitch. Our via(s) are solder masked, however we generally have a percentage of them that the masking is thin enough that
Electronics Forum | Thu Jun 06 02:52:42 EDT 2002 | ianchan
Hi mates, just my 2cents worth... some folks (like us) have product runs that have BGA using no-clean, coupled that with Class3 IPC-A-610 specs, topped with aerospace/military customer defined specs. we end up cleaning NC with a degreaser machine w
Electronics Forum | Tue Jun 25 05:28:45 EDT 2002 | ianchan
Vapour Phase is a "phased out" technology. Hot Air Convection is the commonly acceptable type of Reflow Oven. Some folks are getting good improvements for "IR + Hot Air Convection" (combined) Oven technology. Nitrogen Ovens have their own set of p
Electronics Forum | Fri Jun 28 16:21:03 EDT 2002 | russ
Is that 5 top and 5 bottom zones? We use a 4 zone and a 3/4 zone oven for BGAs and have success. I don't believe that the amount of zones is the issue but what type of profile you can get out of them. I will admit that the large ovens are much eas
Electronics Forum | Thu Aug 01 12:55:41 EDT 2002 | johnw
we run the paste in both air and n2 depending on customer requirements again it run's fairly well in both. Some people say it's better sme say it doesn't make a bit of difference, I'm somewhere in between at the moment. I definately think there's imp
Electronics Forum | Mon Oct 14 17:28:08 EDT 2002 | msimkin
Russ, Thanks for the feedback. Yeh, we are placing them in production using a full ball detect Yamaha placement machine, 5 thou square stencil. etc.etc. The only reason I raised this concern was from a rework point of veiw (actually, the board desi
Electronics Forum | Wed Oct 30 09:16:51 EST 2002 | russ
Low air flow huh. This is interesting, I have a low end machine that has adjustable air flow and I was having some shorting problems awhile back (corners mostly) and my first attempt was to preheat the board up to 170C and then use lower temp to put
Electronics Forum | Wed Nov 13 04:36:46 EST 2002 | iman
does anyone know what environment factors(specifications?) and process control parameters(printer & reflow?) are optimal for running SMT using type 4 and type 5 solder paste respectively? Any pitfalls to avoid? The product we have been asked to use
Electronics Forum | Thu Nov 28 20:37:40 EST 2002 | Dreamsniper
I'm in the process of generating work instructions for our stores and production process with regards to moisture sensitive devices.And I'm a bit confused. I found out that we have many TSOP's, QFP's and BGA parts in sealed bags that have not been op
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