Hierarchy Editor - Change library

No, you can't do this (in general). Only cellViews which don't have a "hard" library binding can have their library binding influenced. Schematic views have a hard library and cell binding - and only the view can be altered. For Verilog textual views, these have a hard cell binding, and the library can be changed (as can the view) - this is because Verilog doesn't have a concept of libraries (really).

So you can control the binding for Verilog textual views by setting either a global library list or an inherited library list (this can be enabled in the cell or instance table, or in the tree view by doing Right Mouse->Inherited Lib List). This then affects the order of libraries bound from that cell or instance (or occurrence if it's an occurrence binding) downwards, but only for instances that have a "free" library binding.

Regards,

Andrew.

Hi Andrew:

    You added the qualified "in general".  Is there a way to accomplish this?  It seems to me that if there is an alternate library/cell/view available (same pins/name etc) that one should be able to use it.

Would a subconfig work?

Thanks,

Terry

Hi Terry,

The "in general" was (I think) because of the fact that you can do it for cellViews with a soft binding (such as the verilog textual views I mentioned before). For various historical (mainly efficiency) reasons, doing a cross-library search on a per-install or per-cell binding basis has never been supported and there are no plans to do so. I must admit I'm not entirely convinced that an explicit re-binding to a different library in the hierarchy editor would be a big performance problem, but there almost certainly would have to be a lot of code that needed changing because this has been an assumption for as long as Virtuoso has existed (25 years; the hierarchy editor (in various incarnations) is a mere 20 years old).

I did wonder whether you could use a config view (alongside the symbol in the first library) as the view to use, with the top cell in the config being a schematic (for example) with the same cell name and pins in another library. The hierarchy editor is happy with this, but various things don't work:

• When you descend in the schematic editor, it fails to open the design marked as the top level in the subconfig
• Netlisting fails unless the view being switched to is in the same library (with the same cellName of course)

Fundamentally there are too many assumptions where only the viewName changes when doing view switching.

One case where you can switch libraries is with physConfigs for layout - the logical hierarchy can be in one library, but the physical hierarchy (the implementation) can be in a different library (this is handled in Configure Physical Hierarchy, which is an extension of the ideas in a config view but for layout purposes).

Regards,

Andrew.