Just last week there was an issue someone had with LED's working on cards that were just reflowed, then shortly after, failing. The failure rate was quite high. Can that person reply as to their remedial action ??? Was the profile temps reached higher than what the leds were designed to withstand ?? Regards TDK -----Original Message----- From: Matthew Lamkin [mailto:[log in to unmask]] Sent: Wednesday, October 06, 2004 1:04 AM To: [log in to unmask] Subject: Re: [DC] Lead-Free Fab_notes With the increase in reflow temperatures, I would imagine that you will have to check all your components can handle the new higher temperatures. I have seen some expand through heating at levels near the top of their permitted temp, let alone going beyond it. The lead free substitutes that I am being offered, while may make for a far flatter finish than HASL etc, are not very good at being resoldered during rework, pads may have to be heated up more, so if there is a component fitted that is liable to be replaced during the boards life, it may pay to increase it's pad sizes slightly to increase adhesion to the laminate (unfortunately that also has the consequence of making more solder to heat up). Matthew Lamkin. -----Original Message----- From: Fred Dark [mailto:[log in to unmask]] Sent: Monday, October 04, 2004 6:00 PM To: [log in to unmask] Subject: [DC] Lead-Free Fab_notes Dear Designer Council, I'm looking to get some information on "Lead-Free" technology... from a PCB designers point of view, what would I have to do different for design and documentation... how would my fabrication notes change for this technology... For a standard Fr-4 material, would this have to be different... along with finishes and etc... I know there is a lot of manufacturing issues with solder paste, solder temp. and more, but from a designers point of view, what will I have to do different... I'm reading up on the technology, but I'm not seeing what to do as far as from a designers point of view... Can someone point me in the right direction for notes, books from a designers point of view... and what ever other info that I would need to know... Thank's as always, Fred Dark Jr. ---------------------------------------------------------------------------- ----- 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 ---------------------------------------------------------------------------- ----- ---------------------------------------------------------------------------- ----- 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 ---------------------------------------------------------------------------- ----- --------------------------------------------------------------------------------- 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 ---------------------------------------------------------------------------------