STEP 3D Model Download Sources

Recommended sources for free 3D models:

1. SnapEDA (snapeda.com) - Largest free library, STEP + symbol + footprint
2. SamacSys / Component Search Engine - Plugin for Altium/KiCad/Eagle
3. 3D ContentCentral (3dcontentcentral.com) - Manufacturer-provided models
4. GrabCAD (grabcad.com) - Community-contributed electronics models
5. Ultra Librarian (ultralibrarian.com) - Free with registration
6. Manufacturer websites - ST, TI, NXP, Analog Devices provide STEP models direct

All models should follow IPC-7351 Level B for maximum case outline.
