Importing gds stream data of the assembly housing packages

OK, if you imported this into a new library and used the automatic layer mapping, it will create a new technology library and a layer mapping file to map the stream layers/datatypes to automatically created layers/purposes in the new tech file (please search in the documentation for "Use Automatic Layer Mapping" for details as to what it does).

If you then try to use an instance of this package in another technology, you're going to be constrained by what layers exist in that technology. The database itself is stored as numerical layer numbers and purpose numbers (and in automatic mode these will correspond usually to the layer numbers/data type numbers in the stream file). If those layer numbers and purpose numbers don't exist in the PDK for the design you are instantiating into, the shapes will vanish (they're still there, but there's no information as to how to draw them). Similarly, they won't get streamed out because there's no information in the layer map you use (typically the default for the PDK technology library) to tell the stream interface which stream layer numbers/data type numbers to map to - so the shapes get omitted on stream out.

If you're just working on the package layout, you could stream out using the same layer mapping that was generated on stream in. 

However, if you're intending on combining this with the IC fabric, you'll probably need to define a custom layer map file which maps the layer numbers/data type numbers onto suitable layer/purposes that are in the PDK. Of course, whether you have suitable layer/purposes will depend somewhat on whether this flow was ever intended by the foundry. The other way could be to create an incremental technology database which references the PDK technology database and adds the definition of the package layers you wish to use, and has a layer map file in the incremental technology library which maps these additional layers to/from stream (of course, you will need to make sure the stream layers you are using don't clash with any of the numbers that the foundry normally uses). If you do this, then you can use this new superset incremental technology database as the technology library for your design and package, and all should work OK - including at stream out.

This all needs thought and careful design and setup. It's far beyond the scope of a quick question in the community forums to talk through all of this and explain how it should be done (especially as it is rather unusual to import the package into Virtuoso and co-design it this way, so I am wary of giving a lengthy step-by-step guide when I don't know all the details). I also don't have the bandwidth to do that level of detailed explanation (the explanation above is lengthy enough!). Contacting customer support would be the better option here - or maybe even the foundry.

Andrew

OK, if you imported this into a new library and used the automatic layer mapping, it will create a new technology library and a layer mapping file to map the stream layers/datatypes to automatically created layers/purposes in the new tech file (please search in the documentation for "Use Automatic Layer Mapping" for details as to what it does).

If you then try to use an instance of this package in another technology, you're going to be constrained by what layers exist in that technology. The database itself is stored as numerical layer numbers and purpose numbers (and in automatic mode these will correspond usually to the layer numbers/data type numbers in the stream file). If those layer numbers and purpose numbers don't exist in the PDK for the design you are instantiating into, the shapes will vanish (they're still there, but there's no information as to how to draw them). Similarly, they won't get streamed out because there's no information in the layer map you use (typically the default for the PDK technology library) to tell the stream interface which stream layer numbers/data type numbers to map to - so the shapes get omitted on stream out.

If you're just working on the package layout, you could stream out using the same layer mapping that was generated on stream in. 

However, if you're intending on combining this with the IC fabric, you'll probably need to define a custom layer map file which maps the layer numbers/data type numbers onto suitable layer/purposes that are in the PDK. Of course, whether you have suitable layer/purposes will depend somewhat on whether this flow was ever intended by the foundry. The other way could be to create an incremental technology database which references the PDK technology database and adds the definition of the package layers you wish to use, and has a layer map file in the incremental technology library which maps these additional layers to/from stream (of course, you will need to make sure the stream layers you are using don't clash with any of the numbers that the foundry normally uses). If you do this, then you can use this new superset incremental technology database as the technology library for your design and package, and all should work OK - including at stream out.

This all needs thought and careful design and setup. It's far beyond the scope of a quick question in the community forums to talk through all of this and explain how it should be done (especially as it is rather unusual to import the package into Virtuoso and co-design it this way, so I am wary of giving a lengthy step-by-step guide when I don't know all the details). I also don't have the bandwidth to do that level of detailed explanation (the explanation above is lengthy enough!). Contacting customer support would be the better option here - or maybe even the foundry.

Andrew

Thank you very much Andrew for your nice explanation, I will study it and follow it and give my feedback to it.

Best Regards