Some time ago I recall some class/tutorial notes regarding the way SPB tools utilize these two subclasses with respect to component placement and constraints definitions as well as interpretation by the 3D viewer. I can't seem to locate those notes now.
I have always used place_bound shapes to represent actual component body dimensions and to create a crude 3D model for visualization of boards with components. With recent upgrade to 16.6, the footprint viewer (within CIS) does not properly interpret my footprints with the 3D heights.
I have noticed that in EMA supplied footprints, many also have dfa_bound shapes defined with height properties. Those footprints appear to reflect an appropriate 3D perspective in the CIS viewer.
Do I need to update all my symbol libraries to include both subclasses and/or why?
Oh - I've also noticed that the 3D viewer within symbol editor is still broken (since v16.3) with respect to inverting the Z-axis display of height information. The positive height properties are displayed downward through the board level padstacks as opposed to top-up. Anyone know of plans to "fix" that some day?
Any tutorial guidance is appreciated!
DFA boundary is used in Allegro Designer in the DFA feature to set package to package spacing. As to why your parts do not show height in the 16.6 Capture footprint viewer I would have to investigate that.
Cadence is aware of the issue with the Height display in package symbol editor and is planning on fixing it. I do not have an excat time frame.
EMA Design Automation
Thank you Bill,
The cheat-sheet I was looking for is regarding the priority order used to set package-to-package spacing rules by the tool, i.e.
With the Capture footprint viewer, the height is displayed on the EMA supplied library footprints and the only difference I can spot is that most of them have both dfa_boundary and place_boundary defined with height properties on both.