A performance-driven placement algorithm with simultaneous Place&Route optimization for analog ICs

Abstract

This paper presents a performance-driven placement algorithm for automatic layout generation of analog ICs. The main innovations of our approach are essentially: (i) an integrated Place&Route optimization algorithm which is able to provide a realistic measurement of the interconnect parasitics, that is a key issue in performance-driven approaches; and (ii) the simultaneous consideration in the cost function of two levels of symmetries: global symmetry with respect to virtual axes and local symmetry affecting groups of cells. The flexibility and efficiency of the algorithm is mainly due to the use of the same slicing-tree representation for placement and global routing, and to the heuristic algorithm we propose for the global routing estimate. The feasibility of the proposed approach has been demonstrated with several practical examples.