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Many of you, our regular readers, are familiar with via structures. These reusable patterns of vias, clines, shape, and keep-out shapes, and return path elements allow you to escape a single pin then replicate that structure (or pattern of structures, if we’re talking differential pairs and similar hierarchical objects) across all similar elements in seconds to reduce design time.
If most of you are familiar with these elements, why, you ask, are we talking about them today, instead of looking at more exciting new features in 17.4? How about because how you design, implement, and reuse them is provided through a redesigned, much easier to use, user interface? Sounds like a great reason to me!
Follow along on our journey to discover what’s changed and how it affects you.
The first thing you’ll notice is that the Route menu commands, previously under the Via Structures submenu, now are found under the Structures submenu. Why the change? Since not all structures are used to via between layers – they could be simple repeated fanout elements with shielding, for instance – the simplified name better captures what these really are: hierarchical routing structures.
17.2 Route Menu’s Via Structure Commands
Don’t let the name throw you. However, keep in mind that with any name change, you may have to make subtle changes to your processes. The menu hotkey, for instance, has changed from V to E; create via structure as a command is now just create structure. Should you have scripts that work with this command, you may need to tweak them.
17.4 Route Menu’s Structures Commands
The via structure defining commands in 17.2 were split into a set of commands: create via structure, create hsvia structure, and struct gen lcomp, depending on the product options you are using. These are now consolidated into a single command (create structure) with a completely redeveloped UI.
This interface still offers the same capabilities, but we have reworked it to help you get the most of the structures you create. Helpful tips and a flow for you to follow are available for each structure type:
Having all in the same form allows you to compare the options to pick the ideal one to address your design requirements. Pick between high-speed and standard structure elements, or design a coil. You do not need to switch commands to create multiple structures of the same – or different – styles.
The updated UI even provides additional screen real estate that makes the fields to define objects more readable.
Above, we have the simpler standard structure options, while below we have the more detailed L Comp page:
You'll find many other updates as well, such as support for the Find by Query tool to filter for, and quickly select, the items to comprise your newly defined structure.
You’ve defined your structures and now need to place them. Are there any differences to be found at this point? Absolutely! See the form below for the place structure command (which replaces the add via structure command from 17.2).
For those of you who have a large library of structures defined, the name-based filter is invaluable to quickly locate the library elements that you want to leverage in the current design. You can still export structures from this design to be added to the reusable library elements if you want. Most of the other fields here should be familiar to all of you, as they’ve been rearranged for readability, but their behaviors have not changed. A description field at the bottom of the form offers you localized guidance very similar to the User Preferences GUI.
I don’t want to spoil the surprise. Come back next week to uncover more exciting additions to 17.4 which will have you eager to move up to the latest release!