Hi, The MAX condition is, IMHO, excessive unless you get a component at MAX conditions. In general the IPC 782 pad dimension are quite large and you could get tomb stone parts. But there are other variable that are involved, placement accuracy and flux properties come to mind first. You can also look into the "Home Plate" design for solder paste apertures though 0201 is getting small from the get go. Sorry, wish I could be of more help. Bob Kondner -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Brad Saunders Sent: Tuesday, July 13, 2010 3:59 PM To: [log in to unmask] Subject: Re: [TN] 0201 footprint requirements Howdy Bill, I was delighted to see Werner's answer on this question. I had done very exhaustive reliability study on solder joint reliability specifically related to footprint design and we concluded exactly what Werner was able to say so eloquently. I found later the footprint also was a political platform and to satisfy a consensus I constructed a formula that would give a bit of pad to the sides and ends. I knew it would not subtract from reliability and -so long as it didn't get to big I was OK- it did allow me to round off pad sizes which is very nice, also I was able to manipulate center spacing which additional benefits. But don't grow that length under your parts... and don't get me going on radius lands verses square. Boston Brad ----- Original Message ----- From: Brooks, Bill<mailto:[log in to unmask]> To: [log in to unmask]<mailto:[log in to unmask]> Sent: Wednesday, July 07, 2010 2:37 PM Subject: [TN] 0201 footprint requirements I am looking for some assistance with the pad geometries for 0201 caps and resistors... Is there or is there not an industry consensus on what the optimum pad geometry should be for them? What I am hearing from our assembly houses differs greatly from what is published in IPC-7351 and the land pattern tool from PCB Matrix. Is the max material condition footprint actually a recipe for tombstoning? What have you folks seen? What do you recommend? Bill Brooks | Datron World Communications, Inc. PCB Designer/Engineer | Office: 760-602-7004| Fax: 760-597-3777 | [log in to unmask]<mailto:[log in to unmask]> 1808 Aston Avenue, Suite 230, Carlsbad, CA 92008 | www.dtwc.com<http://www.dtwc.com/> Performance You Require. Value You ExpectTM ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. 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