Constraint Propagation for Analog and Mixed-Signal Integrated Circuit Design

摘要

While the design of digital integrated circuits (ICs) is largely automated, the design of analog/mixed-signal (AMS) ICs is still dominated by manual tasks. One of the biggest obstacles to further automation is the large number of constraints that have to be taken into account during AMS IC design. They are derived both from the specification and during the actual design process and must be fulfilled before production of the IC can begin. Current IC design tools hardly support working with constraints - they are either not formally described and are therefore only available as export knowledge, or they are not visible in all cells in which they must be considered. This thesis addresses three selected, practically relevant problems of constraint management during AMS IC design: (1) formal description of constraints and their classification, (2) propagation of constraints within the design hierarchy so that they are visible and verifiable in all relevant cells, and (3) influence of constraints on the modeling and storage of design data. By implementing solutions to all three problems, the comprehensive and consistent consideration of constraints in the entire design hierarchy and flow is made possible, thereby overcoming the obstacle described above. The objective of this work is to formalize constraints and integrate them into the AMS IC design process so that they can be considered at all stages of the design. Experimental investigations show the practical suitability of the methods even for complex circuits. Our findings enable the integration and consideration of constraints in all types of design tools - not only for AMS IC design, but after generalization also for any design process.