Electronics Forum | Wed Oct 04 14:14:49 EDT 2006 | russ
Change mfgrs of paste OR better yet use pbfree paste, If you are collapsing the balls on the BGA then you are possibly overheating the paste/flux quite a bit. most lead pastes do not like much more than 230 C. I am assuming that you have a decent p
Electronics Forum | Wed Oct 04 14:18:05 EDT 2006 | C.K. the Flip
The main cause of voids is your flux out-gassing during reflow. Try a little "knee" or slight soak in your thermal profile to dry out the volatiles a bit. Typical soak ranges from 130 deg. C to 170 deg. C for around 30-90 seconds.
Electronics Forum | Wed Oct 04 14:48:49 EDT 2006 | cw
My soak at 150C - 180C for approx. 85sec to 100sec. I believe this is sufficient. I can't change my paste because customer wants to use SnPb paste with SAC solder balls. They claimed that they have sucessful result with other CM. I need to know if
Electronics Forum | Wed Oct 04 16:14:17 EDT 2006 | inds
what is your peak temp.. if you try to go too high say 225-230 deg C there is a fair chance of seeing voids.. depending on your ball size and paste volume you can get a good collapse at temps below 225deg C...
Electronics Forum | Wed Oct 04 16:24:48 EDT 2006 | russ
try Alpha OM5100 this is a noclean paste that we use and have done the same thing you are now, reflowing pbfree with pb paste, we run to max temp of 230C with this paste and use a straight ramp with no soak profile is about 4 mins long from ambiant
Electronics Forum | Thu Oct 05 16:12:09 EDT 2006 | Mario Scalzo, SMT CPE
* Try 1.5C / sec from RT to 165C * Hot soak at 165-175C for up to 2 minutes (I'd start with 60 seconds flat soak.) * 60-90 seconds TAL (I's start with 60) * 230-240C Peak. Thanks, Mario
Electronics Forum | Tue Oct 17 09:27:23 EDT 2006 | SWAG
We had a build that showed a relatively high occurence of BGA voids like you were seeing. It was a very small volume first article that took a long time to get through the line so the paste sat on the boards too long. As we ramped up TACT time in p
Electronics Forum | Thu Oct 05 21:08:02 EDT 2006 | Dman97
Well, the monitor isn't touch screen. The light pen IS the mouse/trackball. If I touch the screen nothing happens. The industrial PC has no PS/2 ports of any kind on it. Perhaps I could splice into the light pen connections and connect a standard tra
Electronics Forum | Fri Oct 06 09:43:30 EDT 2006 | slthomas
Sorry, just reread your post. Nevermind. FWIW, I'd be pretty careful about splicing a different piece of gear into a hardwired connection unless you know that the current and voltage requirements of each item are the same. However, who's to say tha
Electronics Forum | Mon Oct 09 08:05:46 EDT 2006 | Loco
On our SMtech the pen is connected to a special interface card, we do however have the option of just plugging in a normal mouse in the mouse port. On a side note, maybe something is wrong with your pen, you could try contacting supplier computerwar
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