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This answer says it's IPC-7351, but I'm not seeing anything about land pattern dimensions in the table of contents.

I'm wanting to make footprints in Altium and I found the IPC Compliant Footprint Wizard, but I have to manually enter each of the dimensions and I don't know what to use.

Which IPC standard provides land pattern dimensions?

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Nate
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  • It is IPC-7351B: Calculate high resolution IPC-7351B & RoHS compliant land patterns (footprints) directly from component dimensions. – Leon Heller Jan 25 '15 at 16:15
  • There's also the free version of http://www.pcblibraries.com that generates them for you. I think altium is supported. – Some Hardware Guy Jan 25 '15 at 17:37

2 Answers2

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It is in IPC-7351B. I have the original document, not the "B" version, and the information is in Section 3, Design Requirements. The dimensions aren't given directly; instead, there are suggested allowances and tolerances depending on the part size, lead shape, etc. For example, here is a table suggesting how much extra space to give around the component leads:

landpatterntable

As you can imagine, it's not easy to use this document, especially when all you want are land patterns :)

I highly recommend using Library Expert. It packages all of the IPC-7351 recommendations together. The Lite version is free, and it creates IPC-7351-compliant footprints for a bunch of PCB tools, including Altium, OrCAD, Eagle, etc...

You can tell it which Density Level to uses ("Most", "Nominal", and "Least"). This refers to how much the land patterns will protrude from the actual point of connection.

Please see this earlier answer for more info on Density Levels.

Good luck.

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bitsmack
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  • That's showing the pad dimensions? Because I'm looking at IPC-SM-782 (which I just found) and it's showing totally different dimensions for 1608. – Nate Jan 25 '15 at 16:40
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    @Nate Ah, no, I was not being clear. I just rewrote the answer a bit. Please read it again :) – bitsmack Jan 25 '15 at 16:49
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I know this is a very late answer but you would get the dimensions from the MFG spec sheet and fill in the numbers in the Altium footprint tool. Remember you have three choices in the "size" for the footprint. MIN, NOM,and MAX. Most go NOM in my experience unless you have a very small space to work in such as cell phones.

Brad Carter
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