This flow is targeted primarily at a physical package designer who has experience with the Cadence APD/APE tools. The following steps will guide a user through the creation of a set of split rings for use around a complex wirebond die in a package. Originally posted in cdnusers.org by SoCalDude
For our purposes here, we shall assume that your design currently contains the IC around which you wish to create the split ring pattern. It is also assumed that you have an idea where the major breaks in your rings should be (the breaks where the ring will change nets).
1. The first step after opening the design is to create a set of whole rings which may be cut up to form your split ring pattern. For this, one may use the Power and Ground Ring Generator tool, pring wizard.
A. Start by specifying the number of whole rings you will need. As of 15.2, you are able to create as many of these in one session as you desire (up to 12).
B. Pick the ref des for the die around which you want these rings to be placed.
C. For each ring, specify the width, corner type, radius, and the gap between it and the previous ring (or the die edge for the first ring).
D. If any DRCs result from the creation of your ring(s), you will be notified on the final page of the wizard. Correct these before proceeding to step #2.
2. Under the shape global param's Void Controls tab, ensure that the shape suppression value is set to be less than the minimum ring piece size that you will be creating. If unsure, you may set this to 0 to retain all shapes for now.
3. Use the line drawing commands (add line, add circle, add arc, etc) to create lines on the same layer as the shapes. The rings, being dynamic shapes, will automatically void around these lines. Be sure that your line completely cuts through the shape if you want to split a section into two distinct pieces with different nets later.
NOTE: You may wish to set your shape to line spacing on the ring layer to be ½ the desired width for your gap between ring sections when performing this step. If necessary, take note of the original value so you can restore it when finished.
4. Convert each ring you created into a static shape, using the shape change type command. You will receive a warning that this will lose the original shape boundary. Answer yes to this prompt, as that is what we are trying to accomplish.
5. Delete the marker lines that you used to split your rings. They are no longer needed.
6. Reset the DRC and shape suppression values back to their original values prior to split ring creation. At this point, you now have generated a set of split rings, with each piece being distinctly separate and available for assignment to a different net than its neighbors.
7. Change any net assignments to the individual pieces of the ring(s).
8. Convert your shape pieces back to dynamic shapes one last time. Now, the individual pieces can be dynamically voided to add/remove clearances around vias, routing, etc.