Technetters, my question deals with the number of microsections of blind or buried vias, per panel, required by IPC-6012.

For plated holes, one thermally stressed A/B coupon is required per panel. A second A/B coupon, from the corner opposite to that from which the thermally stressed one was taken, is required to be microsectioned in a direction perpendicular to that of the first per panel to check internal annular ring. (I have not been calling for thermal stress of the second A/B.)

Does 6012 require a second microsection coupon for blind and buried vias? (I have collected a number of opinions, and have one of my own.)

I have noticed that MIL-PRF-55110 does not require a second blind or buried vias. As I read it, the requirement is for a single coupon per panel, thermally stressed, for each blind of buried via. MIL-PRF-31032 does not, it appears to me, explicitly address the number of blind and buried microsections required.

Thanks for any comments or insight.

Louis Hart
Compunetics
Monroeville, PA
USA
[log in to unmask]<mailto:[log in to unmask]>
412-858-1272

______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 16.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------