Electronics Forum | Mon Jul 22 02:13:31 EDT 2019 | jandon
some PQFN package configurations have no toe exposed or do not have a continous solderable surface on the exposed toe and a toe fillet will not form. (IPC-A-610F 8.3.13)
Electronics Forum | Fri Jul 19 22:26:32 EDT 2019 | dhanish
Thanks Dave..What is the voids spec for QFN?This is another challenge with the QFN's
Electronics Forum | Fri Jul 19 01:58:30 EDT 2019 | dhanish
May I know what is the requirement for side fillet for QFN?Any information from IPC spec on QFN side fillet?We cant make the solder joint form at the side fillet.
Electronics Forum | Fri Jul 19 13:09:55 EDT 2019 | edhare
Hi, Are you referring to the condition illustrated here? ... https://www.semlab.com/qfn-solder-fillets In this case, the solder was wicked down an attached un-filled PTH via. Ed Hare SEM Lab, Inc.
Electronics Forum | Fri Jul 19 22:25:06 EDT 2019 | dhanish
yes..there is no fillet as shown in the picture..
Electronics Forum | Fri Jul 19 13:02:01 EDT 2019 | davef
Double-check me on this, but I don't believe that A-610 [IPC-A-610] requires side fillets on QFN solder connections, because the sides of most terminations are not plated. Plating on the bottom of the termination is sufficient for a proper solder con
Electronics Forum | Mon Jul 22 13:19:31 EDT 2019 | davef
While we're are it, here's a link to a recent FORUM thread that talk's about BTC standoff height: https://smtnet.com/Forums/index.cfm?fuseaction=view_thread&CFApp=1&Thread_ID=21852&mc=9
Electronics Forum | Sat Jul 20 14:55:55 EDT 2019 | davef
IPC-A-610F 8.3.13 Bottom Termination Components (BTC) ... Thermal plane void criteria shall be established between the manufacturer and user IPC-A-610F, 8.3.14 Components with Bottom Thermal Plane Terminations ... Thermal Plane Void Criteria -
Electronics Forum | Thu Aug 01 05:25:26 EDT 2019 | ameenullakhan
Hi , hope below information may help you. The presence of small voids in thermal pad region is not likely to result in degradation of thermal and electrical performance The combing of smaller multiple voids up to 50% of the thermal pad area, does
Electronics Forum | Fri Jul 15 13:58:32 EDT 2005 | seaK
Our production is putting QFN40 and QFN56 package on board. With 80% opening on terminal, 40% on thermal pad, we found QFN56 100% forming toe fillet, but it does not work out the same to QFN40. We suspect it's because of the weight of component.....
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