Are there any forum administrators in the house? Ron -----Original Message----- From: JaMi Smith [mailto:[log in to unmask]] Sent: Monday, March 26, 2007 6:04 PM Subject: Re: Footprint standards for Polarized components (Diodes) ARRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR RRRRRRRRRRRRRRGGGGGGGGGGGGGGGGGGGGGGGH!!!!!!!!!!!!! (Very Long and Loud Primal Scream) Fine Matthew, do it any way you want to . . . Just don't call it standardized . . . Just don't call it IPC-7351 compliant . . . Just don't cry when someone else works on a revision to one of your Design(s) in the future, and calls you a "stupid moron and a ****ing idiot" and the worst Designer that they have ever run into because you "did it backwards" for some stupid personal reason, and caused untold screwups on some future production run. You are going to do whatever the hell you want, in spite of what anyone else, or what any standards, are going to say, so just go ahead and do it, and stop trying to convince anyone else here in the forum that your are right, because you are not - you are wrong - so go ahead and make your boards the way that you want too, but mark my word, they will come back and bite you in the a** a few years down the road, and all you will be remembered as is the stupid Designer that screwed things up because he was too stubborn and wanted to do it his way and wouldn't play according to Hoyle. And by the way, your successor, who will inherit your Designs after you retire or move to another company, >>>>WILL<<<< "use [your] CAD package (Cadstar) to create the pick & place file." - which will of course be all ****ed up, but he or she will not realize that until after a production run has been made with your ****ed up Cadstar Pick and Place file because you were to stubborn to do it right the first time. You could have started a new Footprint Library and Schematic Symbol Library and fixed the rotation of all of the components involved and redefined pin numbers, etc., in one tenth of the time you have already spent writing about it here in the forum. We are really only talking abour a couple of components here now (you could add and fix others as you go). Quit bitching about it here and just do what you are going to do. I can't leave off here without specifically responding to part of what you said below: > IMO it is incapable of generating an accurate P&P file that includes all > the data. (panel size, fiducials etc). Also component rotations change > depending upon the supplier as it seems that not all suppliers follow the > same standard. If you would CORRECTLY DESIGN your components FOR the P&P file, you WOULD have all of the CORRECT data in the P&P file. Panel size has absolutly nothing to do with individual components or their footprints, as a panel is usually built up as a "step and repeat" of individual boards, and any "pick and place" machine out there today can compensate for "step and repeat", including any necessary "rotation". Fiducials are not necessaruly a problem, since they are generally seperately placed from the component, and if they are critical to the component and it's rotation, then they can be made part of the component footprint itself. As for the last sentance above, respecting changing rotations or non-standard component rotation. THIS IS THE EXACT REASON WHY YOU SHOULD FOLLOW THE COMPONENT ROTATION ADOPTED BY IPC-7351, SO THAT COMPONENT ROTATION IN THE DESIGN WILL BE STANDARDIZED, AND SO THAT >>>ANY<<< MANUFACTURING ENGINEER CAN ADAPT >>>ANY NON-STANDARD<<< COMPONENT ROTATION TO >>>ANY DESIGN<<< . Sorry if it seems as if I am yelling at you - because I am ! JaMi PS. Yes, it is true that some manufacturers do not follow ANSI/EIA-481 when it comes to packaging components in "tape and reel" for "pick and place" machines, but more and more are, and month by month the component manufacturing industry is conforming and coming into line with the existing standards, which is all the more reason why you should. ===================================================== --------------------------------------------------------------------------------- DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil. To temporarily stop/(restart) delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL/(MAIL) Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------------