Electronics Forum | Thu Jan 17 20:17:55 EST 2013 | duchoang
We have got lots of voids at ALL LGA. Anyone has ideas to get rid of this issue or just minimize the size of voids ?. With the same paste, same reflow oven, looking good profile, we don't have that problem with BGA. Thanks.
Electronics Forum | Fri Jan 18 14:39:07 EST 2013 | davef
Main issues with LGA voiding are: * Design * Material selection * Thermal recipe For design, loo here http://blogs.smtnet.com/smt/other/qfn-btc-design-guidelines-thermal-pads-etc/ BR, davef
Electronics Forum | Fri May 09 08:27:35 EDT 2014 | emeto
REduction of center pad is the key as well as the stencil thickness. Having too big opening on your stencil will sometimes lift the part from the pads. Always try to make windowpane and shoot for about 60% of the thermal pad to be covered as start p
Electronics Forum | Fri May 09 09:31:04 EDT 2014 | jorge_quijano
we are placing small QFNs with no major issues, but this one may not seem like a QFN with thermal pad... I'm attaching a picture of the component.
Electronics Forum | Mon Oct 05 16:05:40 EDT 2015 | cyber_wolf
Washing no-clean solder residue out from under BGA's might present a challenge.
Electronics Forum | Tue Mar 08 15:35:43 EST 2016 | fuji_user_2014
I am having problems with LGA solder balls under the devices. Here are some of the details: 1. There are only 2 affected parts @4 locations. 2. The parts are LTM4616EV#PBF and LTM4608AEV#PBF. 3. We are using a ramp soak spike profile. 0-100secs=r
Electronics Forum | Tue Mar 08 15:47:23 EST 2016 | sarason
Maybe your flux in the paste isn't working or simply isn't there in this new batch ? Heat a blob on the end of a soldering iron and smell it (head space analysis)(old chemist joke!) sarason
Electronics Forum | Tue Mar 08 15:55:08 EST 2016 | sarason
Also try monitoring your temperature profile with a temp sensor independent of the machine, maybe your heating element isn't spiking quite as well as it used to ? sarason
Electronics Forum | Sat Nov 11 11:11:28 EST 2017 | spoiltforchoice
One suggestion I have seen for packages like this is to have the device balled first.
Electronics Forum | Fri Dec 01 13:30:08 EST 2017 | kojotssss
Stencil thickness is 4 mil. Via's are plugging from bottom. Gas may be developed under the component? Take Reflow Ovens Thermal Profiling changes? In your opinion?
