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  3. Ignore dummies in PVS using GPDK 45nm [solved]

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Ignore dummies in PVS using GPDK 45nm [solved]

hesaliveJim
hesaliveJim over 1 year ago

I would like to Ignore dummies when performing LVS using PVS.

I'm using the virtual foundry GPDK 45nm (Cadence) to do some research.

I note in this post:

https://community.cadence.com/cadence_technology_forums/f/custom-ic-skill/58057/cdsenv-setting-with-backannotation-in-layoutxl/1393995#1393995

BrendaGray suggests:

lvsIgnore: When set to "true" or checked, it indicates that the dummy should be ignored during LVS checks.

This would do but I'm not sure where to place it within the PVS submission form:

I tried putting it in the Filter options shown above but it is complained and should it be lvsIgnore=TRUE wherever it's put?

I do know that a lot of designers recommend simply updating the schematic but as this is a 'virtual foundry' I see no harm -  in Calibre the option exist.

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  • RobMan
    RobMan over 1 year ago

    So 'lvsIgnore' is a Virtuoso instance property. This is there to influence when to ignore devices relating to Virtuoso Layout Suite XL binding.

    'lvsIgnore' has no direct input into PVS LVS. It is not a rule command, setting or input into PVS LVS. It could however have some influence. Adding this property to a schematic instance and setting the value to true will inhibit netlisting of the instance to cdl. Typically the cdl netlist is used for LVS comparison. Hence with the schematic instance missing from the netlist it is not checked. This property has no bearing or influence on the extracted LVS layout netlist.

    Typically the addition of dummy devices results in these extra devices in the layout. If you choose not to backannotate these devices into the schematic for an LVS match then they need to be filtered from the check. A rule must be added to the PVS LVS rules to achieve this. Please see the the commands lvs_filter_option in

    Cadence PVS Developers Guide --

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  • RobMan
    RobMan over 1 year ago

    So 'lvsIgnore' is a Virtuoso instance property. This is there to influence when to ignore devices relating to Virtuoso Layout Suite XL binding.

    'lvsIgnore' has no direct input into PVS LVS. It is not a rule command, setting or input into PVS LVS. It could however have some influence. Adding this property to a schematic instance and setting the value to true will inhibit netlisting of the instance to cdl. Typically the cdl netlist is used for LVS comparison. Hence with the schematic instance missing from the netlist it is not checked. This property has no bearing or influence on the extracted LVS layout netlist.

    Typically the addition of dummy devices results in these extra devices in the layout. If you choose not to backannotate these devices into the schematic for an LVS match then they need to be filtered from the check. A rule must be added to the PVS LVS rules to achieve this. Please see the the commands lvs_filter_option in

    Cadence PVS Developers Guide --

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