Many thanks to Jeff and Gary for catching the discrepancy and passing the corrected information along to all.---John At 10:32 AM 3/6/97 -0600, you wrote: >I'm not with IPC but I have in front of me IPC-SM-782A Amendment 1 which >was recently released ... There was a correction to IPC-SM-782A section >3.6.2.2 stating a width and length for the necked-down area of 0.25mm >(0.010") and 0.50mm (0.020") respectively. > >As Gary mentioned, I have also _heard_ "the trace should not be larger than >50% of the pad width" but I don't remember ever seeing that in print by >anyone. > >-Jeff- > >At 06:37 AM 3/6/97 -0600, Tomas Garman wrote: >>John; >> >>Your reference is correct, but I believe it is a typo in IPC-SM-782. >>.025mm would be .001in the statement in 782 is "Maximum conductor width >>should be .025mm [.010in]" >> >>Would someone from IPC like to clarify? I believe the .010in figure is >>closer to reality. >> >>Regards >>Tom G. >> >>On Mar 6, 6:16am, john balchunas wrote: >>> Subject: Re: SMTTraces >>> >Date: Wed, 05 Mar 1997 09:02:11 >>> >To: [log in to unmask] (Mike Modrzejewski) >>> >From: john balchunas <[log in to unmask]> >>> >Subject: Re: SMTTraces >>> > >>> >Hello Mike, I came across the following info in Surface Mount Design and >>> Land Pattern standard IPC-SM-782A section 3.6.2.2..."Wide conductors >>> connecting to a land area can act as a solder thief...Narrow the conductor >>> as it enters the land area. Maximum conductor width should be .025 >>> mm....The minimum conductor length should be .025 mm." Hope this helps! >> John >>> > >>> > >>> >At 06:54 AM 3/4/97 CST, you wrote: >>> >> >>> >> >>> >>Hi my name is Michael Modrzejewski >>> >>Iam looking for some information on trace width going into SMT pads. >>> >>Is there any problems with a .025 trace going into a 1206,0805 or 0603 >pads >>? >>> >>IS there a rule of thumb for this ? >>> >> >>> >>MOJO >>>-- End of excerpt from john balchunas >>-- >>Tom Garman KC4WAR >>PCB Designer and Librarian >>Sacred cows make the best hamburger (stolen from a friend) >>Don't force it, get a bigger hammer. >> > > >+ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + >| Jeff Foster [log in to unmask] | >| Engineering Assistant | >| Broadcast Electronics, Inc. http://www.bdcast.com | >+ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + > > *************************************************************************** * The mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text.* *************************************************************************** * If you are having a problem with the DesignerCouncil, please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************