Constraint-Driven Design Methodology – A Path to Analog Design Automation

Physical design for analog ICs has not been automated to the same degree as digital IC design, but such automation can significantly improve the productivity of circuit engineers. Analog design remains difficult to formalize due to a large amount of expert knowledge involved, such as sophisticated constraints that are specified manually and satisfied through manual layout. We therefore propose a constraint-driven design methodology – a suite of algorithms and methodologies to capture key rules governing analog layouts and to produce layouts that satisfy these rules. In this chapter, we identify major challenges in analog physical design, and relate them to constraints. We introduce techniques for constraint representation and highlight the essential components of a constraint-driven design methodology. Finally, we explain how constraint-driven design impacts a typical analog design flow, layout algorithms and the overall physical design methodology.