Genny, Take a look at IPC-A-610C 1.3 specialized designs. In a nut shell it states 1. The document can not cover all components. 2. A decision/agreement needs to be made between the customer and the supplier on acceptability of that component. 3. If there are similar characteristics to a component already in the document, you could use 610 as a guideline to start from. I do not know what the end use application is but I would do some testing to verify that solder on the component body would not have a negative impact on the over all reliability of the component or solder joint. I work with automotive lighting applications and we are constantly testing our customer's new designs and processes for reliability due to the fact there is little or no documentation on the assembly of new components/materials. If there are issues or concerns prior to launch they are addressed with the customer when exceptions can be made. Regards, Ted T. -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Green, Mike Sent: Tuesday, October 28, 2008 11:53 AM To: [log in to unmask] Subject: Re: [TN] IPC-610, 8.2.5.5 I would think that you would have to take an exception on the drawing until IPC -A-610 provides direction for each special case design. Solder touching the component is a defect because most components are not designed to withstand the stress internally of molten solder temperatures. In addition, the solder joint in contact with a case puts the joint subject to the CTE excursions of that case. For example, as a plastic case expands, it pushes against the solder joint causing thermal stress Mike Green Electronic Packaging Design LMCO-Sunnyvale 408-743-1635 One Corporation, One Team -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory Sent: Monday, October 27, 2008 10:13 AM To: [log in to unmask] Subject: Re: [TN] IPC-610, 8.2.5.5 Hi Genny! Sorry it took me a bit to get your picture posted, but you know how Monday mornings can be. I've got it up now though, it's at: http://stevezeva.homestead.com/files/tsfp-3.GIF Steve -----Original Message----- From: Genny Gibbard [mailto:[log in to unmask]] Sent: Monday, October 27, 2008 9:58 AM To: TechNet E-Mail Forum; Gumpert, Ben Cc: Steve Gregory Subject: RE: [TN] IPC-610, 8.2.5.5 I don't know. I've included a graphic. Steve could you post it please? -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Gumpert, Ben Sent: October 27, 2008 5:10 AM To: [log in to unmask] Subject: Re: [TN] IPC-610, 8.2.5.5 Genny, It sounds like you have something that has terminations similar to a QFN/DFN but where the lead frame is not trimmed flush to the component body. Is there exposed metal an the bottom side of the component, or are the leads really coming out of the side of the component? Are you sure that section 8.2.13 is not more applicable? Ben -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Genny Gibbard Sent: Friday, October 24, 2008 6:22 PM To: [log in to unmask] Subject: [TN] IPC-610, 8.2.5.5 Question for the TechNet gurus. The spec in the subject says that solder touching the component body is a defect. But it states that it is allowed for SOTs. We use a component in a TSFP (thin small flat package). The configuration like a 3 lead sot, but the leads are not gullwing - they come straight out of the device and the whole package mounts flat onto the board. It is much smaller than a SOT, on the order of ~1.2mm sq in total area. Does this fit in the definition of a SOT? The recommended layout actually has the pads start under the device body. I'm not sure how you could possibly avoid solder touching the body. In general, why is it a defect for solder to touch the component body for other component types? Thanks so much for your help. Genny --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 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 15.0 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 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 15.0 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 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 15.0 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 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 15.0 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 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 -----------------------------------------------------