Practical placement and routing techniques for analog circuit designs

In this paper, we will present an effective layout method for analog circuits. We consider symmetry constraint, common centroid constraint, device merging and device clustering during the placement step. Symmetric routing will then be performed. In order to have successful routing, we will perform analog-based routability-driven adjustment during the placement process, taking into account for analog circuits that wires are not preferred to be layout on top of active devices. All these concepts were put together in our tool. Experimental results show that we can generate quality analog layout within minutes of time that passes the design rule check, layout-schematic verification and the simulation results are comparable with those of manual design, while a manual design will take a designer a couple of days to generate.