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Looking at the datasheet for component ESD321DPYR, the PCB footprint looks something like this (copy and paste from page 16):enter image description here

However, the footprint I downloaded from Library Loader here, a trusted and reputable website is quite different and looks like this:

enter image description here

The pins in the footprint they provided extend way beyond the outline and appear too big. I also compared against Library Expert Pro to confirm (based on dimensions I inputted from the TI datasheet) and it looks similar to the TI datasheet not the footprint supplied by Library Loader. I'm a novice at this so not sure if I'm missing something or misunderstanding things. I did send an email about this to SamacSys, the company behind Library Loader. Any help is appreciated!

UPDATES/ADDITIONS:

enter image description here enter image description here enter image description here

Thanks all for the info. I guess I didn’t make the distinction that the “mechanical data” section is sperate and has a different purpose from the “land pattern” data section. I’ve uploaded annotated images to get some clarity.

  1. If I understand correctly, the mechanical data provide dimensions for the IC package itself and the pins on the IC. While the land pattern data provide info for the PCB pads. Is this correct?
  2. In the first new image I just added, is it correct that the arrows point to the pads and the outer perimeter of the package? Is this outer perimeter supposed to match the 1.1x0.7 size in the second new image attached, from the mechanical data section?
  3. In the second new image attached, the arrows in red point to the pins and not the pads? The distance between the center of the pins is max of 0.7, while the pins are max size of 0.3 by 0.55? The outer package perimeter has a max size of 1.1x 0.7?
  4. In the third new image, the arrows point to the pads , which have size of 0.6x0.5 and center to center spacing of 1?

Thanks!

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    \$\begingroup\$ Solder pads are created for the intended solder process used. Which are you planning forced air IR reflow or glue and wave solder? infineon.com/dgdl/… \$\endgroup\$
    – Tony Stewart EE75
    Jun 9, 2019 at 16:25
  • \$\begingroup\$ Wider pads are used for wave soldering with both pads making contact at the same time from the narrow side of the board feeding the wave is that side is mostly discrete and passives. Longer narrow pads are used for Reflow when IC’s or fine pitch are used on the same side. Consult with board shop for best advice. \$\endgroup\$
    – Tony Stewart EE75
    Jun 9, 2019 at 16:39
  • \$\begingroup\$ You refer to the first image as a PCB footprint, but it isn't - it's a package drawing. The second image is a PCB footprint but if you'd like anyone to comment in specific terms on how it relates to the package drawing, you should annotate it with dimensions. \$\endgroup\$
    – pericynthion
    Jun 9, 2019 at 17:55
  • \$\begingroup\$ Thanks, I just updated the question based on the feedback provided. Kindly read the question section from the line "UPDATES/ADDITIONS" and below for further follow up questions and clarifications. Thanks! \$\endgroup\$
    – Berry
    Jun 13, 2019 at 21:05

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Page 16 is labeled "mechanical data", and describes the package itself.
Page 17 is labeled "land pattern data", and shows what corresponds to the footprint you've downloaded:

X1SON footprint

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  • \$\begingroup\$ Thanks for pointing that out, I'm still new to this. I just updated the question based on the feedback provided. Kindly read the question section from the line "UPDATES/ADDITIONS" and below for further follow up questions and clarifications. Thanks again for your help. \$\endgroup\$
    – Berry
    Jun 13, 2019 at 21:07

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