Using Canned Free Libraries from Various Vendors

With the free canned PCB libraries out there, you get a solder pattern that only has features that were manually created by someone, and you must add all the features you want in your CAD tool.

Did it come with:

• Silkscreen Outline under the package that is not visible after assembly?
• Silkscreen Outline line width that you use that are consistent with your master library?
• Visible polarity marking for post assembly inspection?
• Is the Polarity Marker the right size, shape and location you want?
• Component and Terminal Outlines so you can see exactly where they are in relation to the pad pattern?
• Terminal Outlines provide visual assistance for the solder joint goals for Toe, Heel and Side.
• Contoured Courtyard Outline that represents your internal design rules for part placement guidelines?
• Courtyard Excess for various packages may differ and range from 0.10 mm to 1.00 mm.
• Was the footprint delivered with the units you use?
• Metric, mils, inches, micrometers?
• What design rules were used for the pad size and space calculations?
• Are they consistent with all the footprints from the same vendor?
• Is the pad shape consistent with your company guidelines?
• Rectangle, Oblong, D-Shaped, Rounded Rectangle?
• Do they always have the footprint you are looking for?
• If not, will they create it for free in the time frame you need it?
• Is the footprint origin on Pin 1 or in the center or offset?
• Are the pads for low profile packages trimmed from under the package?
• Are the pad stack sizes rounded 2 (0.01) or 3 places (0.001) to match your master library?
• Does the footprint come in 3 Tiers for Least, Nominal and Maximum density levels?
• Does the footprint come with the correct solder mask oversize?
• If the footprint has a thermal tab, is the paste mask reduction 60%?
• Does the Paste Mask apertures have at least 0.20 space between them?
• Does the footprint come with a 3D model imported into it?
• Is the Zero Component Orientation (Pin 1 location) consistent with your master library?
• Is the Footprint IPC-7351B compliant or did they just make up the footprint name?
• Or did the supplier use the PCB Libraries, Inc. proprietary Footprint Naming Convention in violation of the PCB Libraries, Inc. copyright?
• If the user changes CAD tools, can they rebuild the new library in minutes?

These are just a fraction of all the things a user must consider when using Stock Libraries. 

V2022 Footprint Expert allows the user to set Options for all of these PCB library features for the creation of 100% consistent library quality.

V2022 Footprint Expert allows the user to save the package dimensions and apply different rules for the batch creation of various libraries for multiple applications.