Difference between revisions of "Talk:PCB Footprints"

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(answer question from 6 years ago, etc. :-/)
 
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== SSOP36 ==
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hi..can someone help me to build SSOP36 footprint for eagle.
 
hi..can someone help me to build SSOP36 footprint for eagle.
 
i don't understand with component dimension from datasheet, such us MAX7301AAX, what is 0.80 BSC mean ?
 
i don't understand with component dimension from datasheet, such us MAX7301AAX, what is 0.80 BSC mean ?
 
why do people make other people dizzy with document annotation?
 
why do people make other people dizzy with document annotation?
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-- anonymous 2008
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"0.80 mm BSC" means that the basic spacing between centers (BSC, also called the pin pitch) on that package is 0.80 mm.
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You are not the first person to wonder what that means.
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[http://electronics.stackexchange.com/questions/37643/what-does-bsc-sq-mean]
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[http://www.altera.com/support/kdb/solutions/rd07152011_585.html]
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[http://www.xilinx.com/support/answers/8393.html]
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[http://www.maximintegrated.com/en/glossary/definitions.mvp/term/BSC/gpk/1119]
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[http://www.actel.com/documents/PackageFAQ.pdf]
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What can you and I do to make things less confusing for the next person?
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I see that the current
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[http://www.mouser.com/ds/2/256/MAX7301-90384.pdf MAX7301 datasheet]
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now links to
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[http://pdfserv.maximintegrated.com/land_patterns/90-0098.PDF SSOP 36 leads footprint pattern],
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neither of which use "BSC",
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so perhaps that's already less confusing?
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The MAX7301AAX is a MAX7301 in a "SSOP" 36 lead package with 0.80 mm pin pitch.
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The distance between the center of pin 1 and the center of pin 18 is nominally 13.60 mm.
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Confusingly, I see that other manufacturers sell parts in what they call a [http://cds.linear.com/docs/en/packaging/SSOP_36_05-08-1640.pdf 36-lead SSOP package] with 0.65 mm pin pitch.
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On their SSOP36, the distance between the center of pin 1 and the center of pin 18 is nominally 11.05 mm.
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--[[User:DavidCary|DavidCary]] ([[User talk:DavidCary|talk]]) 08:56, 25 November 2014 (PST)
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== Contributing ==
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Please follow these simple guidelines for contributing footprints.
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* Standardized packages each get their own page
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* Create a section or sub-section for each variation of a footprint/package
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* Footprints for common components (i.e. diodes) or non-standard packages each have their own section on the page for that component
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* Create a table under each footprint section for footprints with multiple pin counts
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Take a look at [[DIP]] if there are any questions.
  
 
== Cleanup & Reorganization ==
 
== Cleanup & Reorganization ==
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* each version has its dimensions listed, with links to download it for Eagle, gEDA, KiCAD
 
* each version has its dimensions listed, with links to download it for Eagle, gEDA, KiCAD
  
[[User:CodeThatThinks|codeThatThinks]] ([[User talk:CodeThatThinks|talk]]) 11:18, 11 August 2014 (PDT)
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- [[User:CodeThatThinks|codeThatThinks]] ([[User talk:CodeThatThinks|talk]]) 11:18, 11 August 2014 (PDT)
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: That sounds great.
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: A typical footprint library file include dozens of footprints.
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: So if we have one page per footprint, does that mean we link to the same library file on dozens of different pages?
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: That seems unnecessarily redundant.
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: But since no one else has proposed a better organization, let's go with "each footprint gets its own page" for now.
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: --[[User:DavidCary|DavidCary]] ([[User talk:DavidCary|talk]]) 08:56, 25 November 2014 (PST)

Latest revision as of 09:56, 25 November 2014

SSOP36[edit]

hi..can someone help me to build SSOP36 footprint for eagle. i don't understand with component dimension from datasheet, such us MAX7301AAX, what is 0.80 BSC mean ? why do people make other people dizzy with document annotation? -- anonymous 2008

"0.80 mm BSC" means that the basic spacing between centers (BSC, also called the pin pitch) on that package is 0.80 mm.

You are not the first person to wonder what that means. [1] [2] [3] [4] [5]

What can you and I do to make things less confusing for the next person? I see that the current MAX7301 datasheet now links to SSOP 36 leads footprint pattern, neither of which use "BSC", so perhaps that's already less confusing? The MAX7301AAX is a MAX7301 in a "SSOP" 36 lead package with 0.80 mm pin pitch. The distance between the center of pin 1 and the center of pin 18 is nominally 13.60 mm.

Confusingly, I see that other manufacturers sell parts in what they call a 36-lead SSOP package with 0.65 mm pin pitch. On their SSOP36, the distance between the center of pin 1 and the center of pin 18 is nominally 11.05 mm. --DavidCary (talk) 08:56, 25 November 2014 (PST)

Contributing[edit]

Please follow these simple guidelines for contributing footprints.

  • Standardized packages each get their own page
  • Create a section or sub-section for each variation of a footprint/package
  • Footprints for common components (i.e. diodes) or non-standard packages each have their own section on the page for that component
  • Create a table under each footprint section for footprints with multiple pin counts

Take a look at DIP if there are any questions.

Cleanup & Reorganization[edit]

It seems this page could be a lot more than just a list of links to lists of footprints. There are so many different versions of the same footprint, and I'm sure many just getting into electronics find this confusing.

I plan on the following reorganization:

  • each footprint gets its own page, equivalent names redirect to that page
  • each page has a list of different versions, with the ones that work the best at the top
  • each version has its dimensions listed, with links to download it for Eagle, gEDA, KiCAD

- codeThatThinks (talk) 11:18, 11 August 2014 (PDT)

That sounds great.
A typical footprint library file include dozens of footprints.
So if we have one page per footprint, does that mean we link to the same library file on dozens of different pages?
That seems unnecessarily redundant.
But since no one else has proposed a better organization, let's go with "each footprint gets its own page" for now.
--DavidCary (talk) 08:56, 25 November 2014 (PST)