NOTE: The 3D model feature of OrCad PCB Designer(Allegro) is only available for versions 17.2 and above.
To import a 3D model in OrCad PCB Designer(Allegro):
Paste the downloaded .STP file to the default STEP path of Cadence:
In your PCB Editor, click Setup>STEP Mapping...
3. A pop-up window will appear. Select the footprint you would like to add the 3D model in the Available Packages section. Then select the 3D step model you would like to add for the footprint in the Available STEP Models section.
4. Adjust the Rotation X,Y,Z and Offset X,Y,Z if needed so that it fits your footprint.
5. Click Save then Close.
6. Go to Display>3D View and notice that you have successfully imported the 3D model.