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  3. How to define double vias in rules file for VCAR

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How to define double vias in rules file for VCAR

PSRK
PSRK over 13 years ago

 Hi,

 I'm using the below constraint in the vcar rules file  before exporting. The VCAR is placing single via while routing.

    list( '("tsmc18rf" "M2_M1" "symbolic") t)

But I dont know the rule to keep double contact/via in the router .Please help me.

 

Thanks,

Siva

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  • craigth
    craigth over 13 years ago

    Siva,

    What release of Virtuoso and VCAR are you using?

    What do you mean by “vcar rules file”? Do you mean the .do file? 

    In parallel to a response to the questions above, reference the following VCAR commands in the IC615 Virtuoso Chip Assembly User Reference Manual. These commands allow you to specify and control multiple vias during routing.
    • use_via http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccraft/iccraft6.1.5/cmd_circuit/use_via_descriptor.htm 
    • use_array
    •  enforce_use_array_rule http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccraft/iccraft6.1.5/cmd_sw/enforce_use_array_rule_key_set.htm
    You can also reference some good information in the IC615 Virtuoso Chip Assembly User Guide  
    •  Via Arrays and Via Images       http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccausr/iccausr6.1.5/chap7.html#98914 
    • Choosing to use Via Arrays or Via Images       http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccausr/iccausr6.1.5/chap7.html#829052  
    • Via Adjacency Rules for Via Arrays      http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccausr/iccausr6.1.5/chap7.html#828997

    If you mean the oa techFile and/or constraint definition as the “vcar rules file” you should reference the following sections in the Virtuoso Chip Assembly User Reference Manual

    • OpenAccess  http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccraft/iccraft6.1.5/toc/iccraftTOC5.html 
    • Mapping Constraints to Virtuoso Chip Assembly Router  http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccraft/iccraft6.1.5/oa/mapping_constraints_to_vcar.htm 
                oaViaDefArrayValue      use_via class rule (from nondefault routing constraint)  

     

    Regards,   

     

    Craig T.

     

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  • craigth
    craigth over 13 years ago

    Siva,

    What release of Virtuoso and VCAR are you using?

    What do you mean by “vcar rules file”? Do you mean the .do file? 

    In parallel to a response to the questions above, reference the following VCAR commands in the IC615 Virtuoso Chip Assembly User Reference Manual. These commands allow you to specify and control multiple vias during routing.
    • use_via http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccraft/iccraft6.1.5/cmd_circuit/use_via_descriptor.htm 
    • use_array
    •  enforce_use_array_rule http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccraft/iccraft6.1.5/cmd_sw/enforce_use_array_rule_key_set.htm
    You can also reference some good information in the IC615 Virtuoso Chip Assembly User Guide  
    •  Via Arrays and Via Images       http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccausr/iccausr6.1.5/chap7.html#98914 
    • Choosing to use Via Arrays or Via Images       http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccausr/iccausr6.1.5/chap7.html#829052  
    • Via Adjacency Rules for Via Arrays      http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccausr/iccausr6.1.5/chap7.html#828997

    If you mean the oa techFile and/or constraint definition as the “vcar rules file” you should reference the following sections in the Virtuoso Chip Assembly User Reference Manual

    • OpenAccess  http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccraft/iccraft6.1.5/toc/iccraftTOC5.html 
    • Mapping Constraints to Virtuoso Chip Assembly Router  http://support.cadence.com/wps/PA_DocumentViewer/pubs/iccraft/iccraft6.1.5/oa/mapping_constraints_to_vcar.htm 
                oaViaDefArrayValue      use_via class rule (from nondefault routing constraint)  

     

    Regards,   

     

    Craig T.

     

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