Electronics Forum | Thu Sep 25 10:27:45 EDT 2003 | davef
Datum: Many times the requirement for a heat sink is anticipated poorly by the designer. So, adding a clip becomes burdensome and too expensive for a respin. Other times, there is no off the shelf clip for the component, as you say. So, a well des
Electronics Forum | Tue Jul 27 08:55:21 EDT 2004 | Cal
CJ- If I am not mistaken the Zephytronics machines have a money back guarantee if not satisfied. We have boards with huge ground planes and the air bath is the only rework that can do this. We also have found heat guns get hot enough but the heat is
Electronics Forum | Tue Aug 30 09:33:55 EDT 2005 | Slaine
whats the actual failure mechanisum your seeing which balls on the BGAs? my bet is its the ones on the corners, this is mainly due the the large heatsink on the top of the BGA when it starts to get hot it acts as a bi-metalic strip and lifts the corn
Electronics Forum | Thu Oct 20 06:03:23 EDT 2005 | Slaine
during the soldering process on larger BGAs the corners can bend up or down due the large copper heatsink on top expanding quicker than the material the bga is made out of, in the worst cases this can lead to to the balls lifting out of the paste and
Electronics Forum | Wed Dec 21 11:49:50 EST 2005 | dlkearns1
We have small blisters all over the bottom side of a heatsink the measures apprx 4" x 12", flat surface. Is there any chance someone can refer me to some standard or specs for usability, personally I think these little blisters would be ok and not in
Electronics Forum | Mon Mar 13 08:46:49 EST 2006 | geocominc
Yes, All six new (LF ready kit) thermocouples are tested good.I would like to say boards are populated on both side back to back with two heavy PLCC's side by side just like having heatsinks and ground plane.Some Odd design.Next try will be to have a
Electronics Forum | Tue Jan 16 11:24:47 EST 2007 | realchunks
I think John is right. I've seen the same thing (I think, without a picture who knows)on heavy heatsink parts. But I've also seen this happen on larger parts that move right after being wave soldered. I'm talking within a second or two of being so
Electronics Forum | Mon Mar 12 08:59:46 EDT 2007 | davef
Questions are: * You say 'voids', but you describe poor barrel fill. Are you seeing both? * Sometimes designers need to reduce the heatsink effect of large ground and power places, but this usually shows on the two upper corner pins, not all corners
Electronics Forum | Thu Jul 19 17:22:17 EDT 2007 | gregoryyork
You need to dwell the boards longer in the wave as the board is the largest heatsink. Just make sure the flux can take the longer dwell times anything up to 4 - 5 seconds so you may have to shallow your angle as well to around 5 - 6 degrees this will
Electronics Forum | Fri Nov 30 16:41:18 EST 2007 | stevek
Does anyone have any experience with the Amkor Fusion Quad package? I'm wondering about the coverage of the heatsink slug and it floating the interior leadless terminations apart. Any designers have any experience escape routing the underpart/inter
