Hi Dave, that's fine Many thanks Best Regards Gabriele -----Messaggio originale----- Da: TechNet [mailto:[log in to unmask]] Per conto di David Hillman Inviato: lunedì 5 marzo 2018 20:50 A: [log in to unmask] Oggetto: Re: [TN] Bottom Termination Components (BTC) Voiding Limits Hi Gabriele - the IPC BTC Voids task group is coordinating with the IPC-7093 specification committee so that both specifications are in sync. Just as the JSTD-001 has the BGA void requirements and the IPC-7095 specification contains the BGA void design aspect/assessment guidance, the JSTD-001 and the IPC-7093 specification will have a similar relationship for BTC voiding. Dave On Mon, Mar 5, 2018 at 11:26 AM, SALA GABRIELE <[log in to unmask]> wrote: > Many Thanks Dave, > > are the BTC Task Group (5-21h ? ) doing same void limits assessment > for the coming IPC-7093 A Review ? > > Best Regards > Gabriele > > -----Messaggio originale----- > Da: TechNet [mailto:[log in to unmask]] Per conto di David Hillman > Inviato: domenica 4 marzo 2018 01:54 > A: [log in to unmask] > Oggetto: Re: [TN] Bottom Termination Components (BTC) Voiding Limits > > Hi Wayne - you have good timing with your question as I can give you > the latest info from the IPC committee meeting last week. The JSTD-001 > committee had a comment submitted asking for void criteria for BTCs. > A small task group with global representation from several industry > product segments was formed to review the issue. We reviewed the issue > with data resources from consortia, IPC and SMTA resources. We had > one very specific > conclusion: Any void criteria that would be put into the JSTD-001 > specification would be addressing solder joint integrity only. Many > BTCs have either thermal or electrical functional needs which is a > design issue that should be addressed during the product design phase. > Here is what the task team responded back to the JSTD-001 committee with: > > "The JSTD-001 QFN Void Criteria task group recommends that a "request > for data" be issued as a review of the current available industry data > was found to not be sufficient to establish a data based maximum void > criteria for solder joint integrity. The voiding criteria requirements > pertaining to the functionality of a QFN or other Bottom Terminated Components (i.e. > thermal or electrical performance) are a design function and not part > of the IPC-JSTD-001 specification scope. The "request for data" > responses should be sent to the QFN Void Criteria task group by > October 31st, 2018 so that they can be reviewed prior to the 2019 IPC > JSTD 001 APEX committee meeting. The JSTD-001 QFN Void Criteria task > group will provide a void criteria recommendation to the IPC JSTD 001 > committee based on the data submissions at the 2019 IPC JSTD 001 committee meeting." > > The void number you listed - especially the 25% - have little to no > technical data justification in terms of solder joint integrity.The > JSTD-001 BTC Void task group is looking for DOE/test/investigation > data and there will be a recommendation to the JSTD-001 committee for > review at the > 2019 committee APEX meeting. I understand that seems like a long time > but any criterial that is put into the JSTD-001 specification must be > done based on data as those requirements results in costs to the industry. > > A number of OEMs verbally committed to providing BTC void data to the > JSTD-001 BTC Void task group so I am confident the issue will be > resolved within the year. If anyone has data they would like to > submit to the task group, please send it to me and I'll make sure it > is included in the data review. > > Let me know if you have any additional questions. > > > Dave Hillman > IPC JSTD-001 BTC task group lead > Rockwell Collins > [log in to unmask] > > > On Sat, Mar 3, 2018 at 6:18 PM, Wayne Showers < > [log in to unmask]> > wrote: > > > I do not know of an IPC criteria on this. I have seen 25% (The BGA > > criteria) cited, but this is not, to my knowledge accurate. > > The limits I have used in the past are 50% Coverage with no void > > exceeding 15% in the center and no more than 10% anywhere else. > > I also used a 70% Coverage and 10% Void criteria for a very heat > > sensitive application. > > > > Question 1: Is there now a citable IPC criteria? and if NO, Question > > 2: What are some of this groups recommended criteria? > > > > Thanks and Regards, Wayne Showers, NPI/Technical Manager, 4Front > > Solutions > > > > > --- > Questa e-mail è stata controllata per individuare virus con Avast > antivirus. > https://www.avast.com/antivirus > > --- Questa e-mail è stata controllata per individuare virus con Avast antivirus. https://www.avast.com/antivirus