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*Footprint Graphics* or *Land Patterns*?

Clive Maxfield
11/16/2010 09:35 PM EST

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antiquus
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re: *Footprint Graphics* or *Land Patterns*?
antiquus   11/19/2010 4:28:46 PM
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Some time ago, when I did PCBs by hand with a light table, we said "dolls", corresponding to Mr. Olson's footprint; the land pattern was implied. These were imprinted plastic sheets, die-cut to the outline of the components, which were adhered to a large clear plastic sheet. Another sheet was overlayed, and black tape used to complete the circuit routing. It is possible that the name was a derivative of "models", shortened to "dels", then vulgarized to "dolls". It is also possible that these plastic stick-ons were similar to the Barbie dress-up toy, and a number of other games. In those toys, plastic cut-outs adhere to a background, allowing the child to complete a picture. Afterwards, the stick-ons could be easily peeled up and stored for later play. Freud could have a field day with this one.

Max The Magnificent
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re: *Footprint Graphics* or *Land Patterns*?
Max The Magnificent   11/18/2010 3:59:48 PM
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"So far no one has called me an accented immigrant!" I'm glad to hear it -- if they did they would have me to answer to! :-) [By the way, I'm an immigrant myself -- I'm from the UK -- and I still have my English accent (grin)]

Yosal
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re: *Footprint Graphics* or *Land Patterns*?
Yosal   11/18/2010 3:52:50 PM
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The definition Max explained is technically correct. However I have used the term "footprint" for both the component and the PCB land pattern this way: "the components footprint is..." or "the PCB footprint for this component is..." So far no one has called me an accented immigrant!!

Max The Magnificent
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re: *Footprint Graphics* or *Land Patterns*?
Max The Magnificent   11/18/2010 2:50:18 PM
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Decals? Give me strength!

Michael.Attenborough
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re: *Footprint Graphics* or *Land Patterns*?
Michael.Attenborough   11/18/2010 9:24:43 AM
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Yes, it makes sense to distinguish footprints (component outlines) from land patterns (solder pad layouts), but in practice, when using PCB layout tools these are drawn together as an entry in a library of footprints (or other name!). I've not heard of any PCB design software that can handle the component outline and the pads separately. Oh, and the PADS software package calls them "decals".

Duane Benson
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re: *Footprint Graphics* or *Land Patterns*?
Duane Benson   11/16/2010 11:45:54 PM
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I've also heard the terms "library parts" and "library components" used in reference to the actual code in the CAD software. Those along with "land pattern" and "footprint" seem to be pretty universally used interchangeably in my world. Generally, when I've been speaking with someone who looks at things more from the perspective of the chip, it's a foot print or land pattern. From those in the EDA world, it tends to be library part or library component. It drives me nuts and thus I do like the idea of standardizing on one term. I pick "footprint." - just kidding. "Land pattern" sounds good to me. I'll do my best to promote that as the standard. I find it an interesting phenomenon how companies frequently end up with their own vocabulary. It's not just in engineering. Many areas of the business do this. Spin-offs seem to follow the original company's dialect. You'd think we would all be taught the same vocabulary in college and would take that with us, but in practice, that idea seems to fall flat in the face of reality.

Max The Magnificent
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re: *Footprint Graphics* or *Land Patterns*?
Max The Magnificent   11/16/2010 10:26:34 PM
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I wasn't asking you (grin)

Jack.Olson
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re: *Footprint Graphics* or *Land Patterns*?
Jack.Olson   11/16/2010 10:19:29 PM
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Yes Max, with our subtle influence and occasional well-directed questioning, "We Control the Language of Electronics"! MwaHaHahaha.... Jack p.s. No, I refuse to list any other terms for land patterns, because we want to converge on the term L A N D P A T T E R N S ! ! ! All else simply falls short of our struggle towards a common terminology. Get with the program, my friend. (smile)

Max The Magnificent
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re: *Footprint Graphics* or *Land Patterns*?
Max The Magnificent   11/16/2010 9:48:02 PM
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OK, so some of the terms used are footprints, geometries, land patterns, and cells. Are you aware of any others?

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