Some boards consist of memory ICs, lots of them, for instance mass memories. Typical for these boards is that all IC packages are all the same, and the only components needed except for memory packages are filter caps, bypass caps and coupling caps, and biasing resistors. In such a case the parts are automatically routed in a symmetric way, like all Xs to the north, all Ys to the south etc. Because it's the simpliest way. But...some boards are impossible to route that way, e.g. microwave boards. In such a case the orientation and the placement is many a time to 100% dictated by the microwave functions. So, there are different disciplins, and a common standard way is impossible. It should be added, that some CAD guys have the same driver as had Albert Einstein: " If a theory or an equation is beautiful, it is probably correct". These CADers think likewise: " The best and most reliable boards are the beautiful ones". There may be a lot of truth in that statement. Ordnung macht frei? Inge -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Green, Mike Sent: Wednesday, February 28, 2007 8:59 PM To: [log in to unmask] Subject: [TN] Component Orientation Survey When you design boards, do you: -lay out similar polar components oriented in the same direction for ease of manufacture regardless of the shortest routing or -lay out each component oriented in the best position for routing regardless of the orientation of other similar parts? We have a difference of opinion as to which is more prevalent practice. --------------------------------------------------- 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- 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 847-615-7100 ext.2815 -----------------------------------------------------