Length matching in detailed routing for analog and mixed signal circuits

Abstract Heterogeneous integration in modern System-On-Chips (SOCs) drives the design automation process for analog and mixed signal circuit components, where matching constraints for certain analog signals are critical for correct functionality. This paper presents a detailed routing solution for analog nets with the single-layer length matching constraint called LEMAR, i.e., a single-layer LEngth MAtching Router. LEMAR is a gridless router using a non-uniform grid routing model to ensure the length matching constraint. LEMAR has the following features: (1) an effective routing model is used for layout partitioning and wire detouring, (2) detouring patterns are presented to obtain the given detouring length, and (3) an enhanced A ⁎ search algorithm along with backtracking technique is presented for finding a routing solution with the length matching constraint. Experimental results are promising.