Designing portable module generators using the Alliance CAD system

The authors describe the design steps of portable generators for CMOS circuits. Starting from a parameterized behavioral description to obtain a layout, the methodology indicates how to specify, build and validate the layout view of parameterized module generators. This methodology uses Alliance CAD system tools for both generation and validation. The layout placement uses a tiler and leaf cell approach to achieve high densities. Software portability is ensured by the use of the general purpose C language as tiling language. Process independence is warrantied by the use of a fixed grid symbolic layout methodology for leaf cell design. Seven CMOS generators have been successfully designed following this methodology