Explicit Expression and Simultaneous Optimization of Placement and Routing for Analog IC Layouts

Our target is automation of analog circuit’s layout, which is a bottleneck in mixed-signal’s design. We formulate the lay-out explicitly considering manufacturing process, and propose an algorithm that consists of simultaneous expression and op-timization of placement and routing. The key is that all the cells and wires are represented by rectangles. The algorithm is combined into a commercial tool, and the performance con-vinced us that the utilization shortens the design time.