Analog Placement and Global Routing Considering Wiring Symmetry

Yu-Ming Yang and Iris Hui-Ru Jiang
National Chiao Tung University


Abstract

Unlike the mature and highly automatic flow for digital layout generation, the existing method to generate an analog layout is far from automatic because it highly depends on the designer‘s expertise. Prior endeavors are mainly dedicated to analog placement because they consider only the device symmetry constraint. This paper is the first work raising the wiring symmetry issue to analog layout in literature: wiring symmetry is as crucial as device symmetry. Hence, we propose an analog placement and global routing algorithm to consider both types of symmetry constraints. During placement, we utilize the device folding technique to enhance the flexibility and feasibility on symmetry. Our results show that our algorithm can produce a promising initial layout to speed up the analog design process.