How do I display the cell instance names in KLayout?

When I open a GDSII, I can see all of the layers and the text layer gives me the pin names. Can I select a specific cell instance in the design and have it highlighted in the layout? Or, is there a way to have KLayout display all of the instance names?

Comments

  • edited July 2022

    You mean something like this?

    I just pressed "1" to select the first level of hierarchy only. More options are here:

    You can also use "Select Top Level Objects" from the "View" menu - if enabled, you will select instances rather than shapes inside the cells.

    Matthias

  • edited July 2022

    What is your use case ?

    Gds and oasis don’t have a syntax for instance or net names. P&R tools or def2gds converter have options to convert instance/net names into either TEXT on a certain layer:datatype or store it as properties.

    For tapeout gds/oasis you don’t need instance or net names and blindly adding them will increase the filesize and read/write times. Especially when all filler cells instance names get written too. Or in the case of net names with gds, you’ll have the same net name TEXT for every net segment. Oasis will use a TEXT reference table and is not as affected.

    So in short, if you want instance and net names, use you p&r tool, or a tool that reads def, don’t use gds/oasis.

    Or use a tool that reads post lvs extracted/compared databases, which also contains the leafcell connectivity. But these databases are proprietary.

  • Not sure this is practical given the GDSII format, but in
    "Brand X" you can place texts in a layout which will be
    evaluated and display that evaluated result. One option
    being something like [%instName] (I'd have to get back
    to a job where I'm provided BrandX access, to get real
    syntax, and it's also involving label properties that say
    how to evaluate, ilExpr, nlpExpr, etc.)).

    But anyhow, wonder if regular cells (possibly) and PCells
    (more likely, as they are evaluated individually for properties)
    would display what you want, if you added such a
    "property reflection text" in their layouts. That will display
    top to bottom I expect (maybe then a "TMI problem"?).

    I'm pretty sure the instance properties are there, how to
    get them evaluated for display I dunno.

  • Thank you for the responses; I'll give you more details. I've used the OpenLane flow to do the place-and-route and to generate a GDSII and a DEF. It would be helpful to see the cell instance names as they are displayed in the image from Matthias but I cannot get Klayout to show such a view. Because I've used OpenLane, there is only one layer of hierarchy. I've tried to import the DEF and the LEF into Klayout, using the

    Macro not found in LEF file: sky130_fd_sc_hd__diode_2 (line=144, cell=, file=rsacypher.def)

  • Ah, I see now that Display -> Top Level Only allows you to see the cell instance names, just as Matthias suggested. Thank you.

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