Here's what I do for component creation:
1. Draw the Place_Bound shape the same size as the nominal assembly outline; no expansion and no accounting for pads.
2. Set a property for the minimum and maximum component height or just go with nominal as the max.
3. Draw rectangles (or whatever) for each pad that extends beyond the body of the component. I'd start with a single pad so I
could give it a low height, 25 to 50 micrometers as you are representing the height of the copper above the outer dielectric
layers. Copy that pad wherever it's needed. You don't want to go back and edit every shape for the height so do that first and
then make the copies.
4. Add a DFA property to the "Drawing". Let me walk you through this part.
Figure 1. A typical legacy 0402 footprint showing pads (green) part outline (red) and Package_Geometry Place_Bound_Top layers. Three new
Place_Bound shapes will represent the component and the two pads for a more precise 3D image and/or MCAD export. The DFA process will
be where component spacing rules are enforced.
In order to get to the little window at the bottom, you have to run the Edit > Properties command and then click on the Find
by Name option at the bottom of the Find Filter. To begin with, it usually shows the Symbol option but you have to go to the
bottom of the pull-down and select Drawing. It's difficult to find this just by poking around but you get used to it.
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Smart Placement Using Design for Assembly Tools
