Application specific integrated circuits (ASICs) are ubiquitous in modern society, with their high performance, low power, low area characteristics aptly utilized in state-of-the-art electronics and devices. As technology nodes scale, however, it becomes increasingly difficult to bring innovation to circuit systems, as the complexity of design rules and the substantial impact of layout parasitics not only delays time-to-market, but is also more expensive. Emphasis is therefore placed on improving the ASIC design flow, with the primary focus of addressing inefficiencies in this manual and iterative process. The implications of faster ASIC development are far-reaching, allowing for rapid prototyping and better scaling in complex and large System-on-Chip designs, reducing overall cost. Improving the chip design process, however, is challenging, as the iterative circuit, layout, and verification stages heavily involve circuit designers, who often use circuit intuition to dictate crucial decisions. Tools that accelerate the chip design process must therefore consider the unique constraints posed by the ASIC domain in order to be practically utilized by circuit designers.

This thesis presents a method for analyzing the efficacy of automated ASIC design tools, specifically by assessing the accuracy, practicability, automation, interpretability, generalizability and run-time efficiency of the algorithm. This is established by presenting one in-depth case study and two projects where machine learning can be used to address inefficiencies in ASIC design, and include: 1) an analog circuit design framework that uses reinforcement learning (RL) to size parameters for a given circuit topology to meet a target specification, 2) an analog sub-clustering tool that uses graphical convolutional neural networks (GCNNs), and 3) using convolutional neural networks (CNNs) to detect defects in circuit yield. The goal is demonstrate that machine learning techniques can not only be successfully used for these three applications, but can be comprehensively analyzed to obtain practical and feasible solutions in circuit design.

Specifically, the results of the RL analog circuit framework show that this solution achieves state-of-the-art run-time efficiency across six unique circuit topologies of varying complexity while considering layout parasitics. Additional analyses is also conducted to explain the decision-making of the algorithm, establishing that the obtained performances are explainable and analyzable in the context of circuit design. Furthermore, for several non-linear circuits, the algorithm obtains initial designs that are better than that of an expert, providing potential for better intuition into the boundaries of performance for these circuits.

The GCNN framework for analog sub-clustering project demonstrates that high run-time efficiency with over 91% accuracy can be achieved while being fully automated, requiring no input from the designer for classification. In addition, the algorithm successfully scales to a variety of analog circuits, which is crucial in establishing practicality. The yield defect detection framework using CNNs shows that ML can be applied to a post-silicon application, successfully resulting in identification of yield defects in real and noisy scan diagnosis tests while reducing the layout search space significantly.




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