Analog layout retargeting with geometric programming and constrains symbolization method

To satisfy the requirements of complex and special analog layout constraints, a constrains symbolization method based on geometric programming for analog layout retargeting is presented in this paper. The approach is to build symbolic template for layouts, then uses geometric programming (GP) to achieve new technology design rules, implement device symmetry and matching constraints, and manage parasitics optimization. The GP, a class of non-linear optimization problem, can be transferred or fitted into a convex optimization problem. Therefore, a global optimum solution can be achieved. The symbolization method ensures the layout retargeting automatically. The efficiency and effectiveness of the proposed algorithm, as compared with the other existing methods, are demonstrated by a basic case-study example and a two-stage Miller-compensated operational amplifier.