Options Overview

The Footprint Expert uses option files (.OPT extension) to allow you to apply a consistent set of library-rules and preferences to one or more FPX files (component data files). By separating the component dimension data (in FPX files) from the rule-sets (in OPT files), the Footprint Expert enables you to use the same part database and quickly generate multiple libraries that reflect different manufacturing, assembly or customer requirements.

Since component package dimension data in FPX files is relatively stable, you just maintain your FPX library and keep adding new parts as needed. The footprint generation rules are stored separately in OPT files, giving you flexibility to modify entire libraries when your requirements change for any reason. By separating options from part data, you can regenerate an entire library with updated rules (by simply switching OPT files) without re-entering the component data.

Option files make it easy to maintain multiple footprints for the same package - e.g., one for "least density" manual assembly, another for "most density" automated pick-and-place, or one for wave-solder vs reflow. They also allow for standartization across your company: distributing a common OPT file so that all users generate footprints in a consistent style and format. Used effectively, option files keep your footprint libraries organized and easier to manage.

There is no limit to the number of option files (.OPT) you can create, nor to the degree of customization you can apply. For example, you might maintain one OPT file for "least density" assembly, one for "nominal density", another for "most density", plus additional ones for wave-soldered boards, flex/rigid boards, automated optical inspection (AOI) tolerances, or specific customer standards.

When you open the Footprint Expert, you can use the built-in default options, choose the FPX file (component data) to use, or create/use your own custom OPT file. You can also choose which default option file to use each time you start the Footprint Expert. OPT files may be stored centrally (on a shared network drive) so that all users in your organization access the same rule sets, but ultimately should be run locally. For centrally stored OPT files, you should control edit rights (read only for most users) so that library generation stays consistent across users.

Within Footprint Expert, you'll see various categories of OPTIONS (OPT) settings. While the shipped software may include one or more default OPT files, you are encouraged to save your own customized versions via "File" > "Save As" and specify an .OPT filename for your organization's needs. For reference, here are some of the major types of OPT files / categories you will likely encounter:

• Options modeled after IPC-7351B and IPC-7352
• organization-specific (Custom) OPT files - You can create OPT files tuned to a manufacturing scenario and suffix convention to label the footprints accordingly
• Console Options (.OPT) - These store user-specific settings such as layer visibility, colours, layer display order, window layout and other interface preferences; these are often unique per user, and typically aren't used for library generation rule-sets

Naming conventions for footprints may incorporate suffix characters (for example "W" = wave solder, "F" = flex board, "L/N/M" for density levels) given by your OPT file naming/footprint-naming rule. This helps you distinguish footprints generated for different process flows. Examples of Suffix Characters to label footprint names:

• Footprint Name + L = Least Density Level
• Footprint Name + N = Nominal Density Level
• Footprint Name + M = Most Density Level
• Footprint Name + W = Wave Solder (bottom side SMD)
• Footprint Name + F = Flexible (solder mask defined pads)

Considerations for using and sharing OPT files throughout an organization:

• Store all canonical OPT files in a centrally accessible location (e.g., network drive or version-controlled repository).
• Enforce read-only access for the general user base; allow only specified librarians/admins to update the rule sets.
• Include a date or version in the filename (for example LibraryRules_V1_2025-10-28.opt) so that you track when the rule set was last amended.
• Maintain documentation or release notes for each OPT file indicating what rules were changed/new in that version (e.g., “Changed wave-solder pad clearance to 0.20 mm”, “Added suffix _W for wave”, etc.).
• Keep your FPX (component data) library and OPT files aligned through good version control: even if the component set remains unchanged, generating footprints with outdated rules may lead to non-compliance with current manufacturing practices.
• When you update an OPT file, you can batch regenerate the library using that new rule set to ensure all footprints are brought up to date.