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Abstract Generator : tech file and origin in LEF file

samung

Hello !!

 

I am generating a LEF view with Abstract Generator Tool, from a layout.oa, for a simple inverter cell (up to M1 layer).

I have the following lines in the generated LEF view :

MACRO test_iv_LayoutToCEL

  CLASS CORE ;

  ORIGIN 0.18 0.24 ;

  FOREIGN test_iv_LayoutToCEL -0.18 -0.24 ; 

 

Actually, I would like to have ORIGIN 0 0 ; 

 

How should I do ? Do I have to  add some lines in the tech file or to specify something in the Abstract generator ?

 

Screenshot in attachment. 

 

Thanks !!

 

P. 

StdCell_origin_layout_to_LEF.pdf

  •  Hi Samung,

    you can change the data in Virtuoso by  clicking edit->advanced->move origin.

    But, if you are converting any place-and-route data to other environments (where the data uses a different origin) your layout will get messed up.

    Remember that LEF/DEF based tools always use the lower-left as an origin (independent of orientation) so you shouldn't need to change anything.

  • Ah ok, actually, the PRBoundary layer exists already in my layout.oa (as an Object). So I said to Abstract Generator not to generate any boundary, because it was already existing.

     

    LEF result is GOOD :

     VERSION 5.6 ;

    BUSBITCHARS "[" ;

    DIVIDERCHAR "/" ;

     

    MACRO test_iv_LayoutToCEL

      CLASS CORE ;

      ORIGIN 0 0 ;

      FOREIGN test_iv_LayoutToCEL 0 0 ;

      SIZE 0.36 BY 1.96 ;

      SYMMETRY X Y ;

      SITE core ;

      PIN A

    ...

     

     

    Thanks !!

     

    Pierre 

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