The Design Of Power Integrity Pre-Layout Simulation Tools

With the rapid development of integrated circuits, more and more seriouschallenges exist in design of power delivery network due to the rise of issues in powerintegrity. Engineers need a useful power intergrity simulation tool to help them, but themain power integrity simulation softwares cannot satisfy the needs of all engineers. Sowe need a new power integrity simulation software which runs fast with high accuracyand occupies little resources. What’s more, the price is suitable.In this paper, we study classic methods. In order to solve the re-design problemcaused by manually choosing the number of decouping capacitors, we use the PDN’stheory and propose an automatic selection method based on adapted genetic algorithmsfor selecting the number of decouping capacitors. This method mimics the process ofnatural selection which was presented by Darwin’s theory of biological evolution, thecase in which the total number of decouping capacitors is the lowest can be found andthe target impedance constraint is satisfied in order to achieve the automatic selectionand reduce the cost.By the simulations, we find that our design method is feasible for practicalapplications, has high stability and can achieve excellent results. Using this method, wedesign a power integrity pre-layout simulation software which runs very well. Theobtained impedance curve of power delivery network is flat. The simulation resultscompared with the result given by a full-wave simulation soft wave for PCBdemonstrates that this method could attain the requirement of engineering well.