Hi Ted, Padsizes you can find in IPC-SM-782 or IPC's online footprint calculator. 12 mil width is standard, anything smaller than that may result in problems with paste printing. This leaves hardly any space for a good solder mask stripe, therefore it is quite common to have one large soldermask window around each row of pads, although some would argue that you need soldermask between each individual pad to get good gasketing of the stencil while printing solder paste. You may need the inner layers for the fan-out pattern, but that doesn't mean you need via-in-pad. When possible use ordinary via's for this. Hope this helps. Daan Terstegge Thales Communications Unclassified mail Personal Website: http://www.smtinfo.net >>> [log in to unmask] 12/14/03 02:59am >>> Hi all, Want to find out what pad size and solder mask opening are people using for .5 mm pitch components? Since the pad size is so small, it is a must to use solder mask define pads? Are people using via-in-pads to get traces out or just using the outer layers? Thanks all in advance. Ted Kong. __________________________________ Do you Yahoo!? New Yahoo! Photos - easier uploading and sharing. http://photos.yahoo.com/ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------