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Leveraging Machine Learning for Gate-level Timing Estimation Using Current Source Models and Effective Capacitance

Published: 06 June 2022 Publication History

Abstract

With process technology scaling, accurate gate-level timing analysis becomes even more challenging. Highly resistive on-chip interconnects have an ever-increasing impact on timing, signals no longer resemble smooth saturated ramps, while gate-interconnect interdependencies are stronger. Moreover, efficiency is a serious concern since repeatedly invoking a signoff tool during incremental optimization of modern VLSI circuits has become a major bottleneck. In this paper, we introduce a novel machine learning approach for timing estimation of gate-level stages using current source models and the concept of multiple slew and effective capacitance values. First, we exploit a fast iterative algorithm for initial stage timing estimation and feature extraction, and then we employ four artificial neural networks to correlate the initial delay and slew estimates for both the driver and interconnect with golden SPICE results. Contrary to prior works, our method uses fewer and more accurate features to represent the stage, leading to more efficient models. Experimental evaluation on driver-interconnect stages implemented in 7 nm FinFET technology indicates that our method leads to 0.99% (0.90 ps) and 2.54% (2.59 ps) mean error against SPICE for stage delay and slew, respectively. Furthermore, it has a small memory footprint (1.27 MB) and performs 35× faster than a commercial signoff tool. Thus, it may be integrated into timing-driven optimization steps to provide signoff accuracy and expedite timing closure.

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      cover image ACM Conferences
      GLSVLSI '22: Proceedings of the Great Lakes Symposium on VLSI 2022
      June 2022
      560 pages
      ISBN:9781450393225
      DOI:10.1145/3526241
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      Published: 06 June 2022

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      Author Tags

      1. current source models
      2. effective capacitance
      3. machine learning
      4. miller effect
      5. resistive shielding
      6. timing analysis

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      • European Regional Development Fund (ERDF) and Greek national funds - Operational Program EPAnEK - call RESEARCH-CREATE-INNOVATE

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      • (2024)GCS-Timer: GPU-Accelerated Current Source Model Based Static Timing AnalysisProceedings of the 61st ACM/IEEE Design Automation Conference10.1145/3649329.3655983(1-6)Online publication date: 23-Jun-2024
      • (2024)Accurate Interpolation of Library Timing Parameters Through Recurrent Convolutional Neural NetworkIEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems10.1109/TCAD.2023.331699143:1(244-248)Online publication date: Jan-2024
      • (2024)A learning-based method for performance optimization of timing analysis2024 20th International Conference on Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design (SMACD)10.1109/SMACD61181.2024.10745408(1-4)Online publication date: 2-Jul-2024
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      • (2024)Stage Delay Calculation Method Considering Effective Capacitance2024 7th International Conference on Electronics Technology (ICET)10.1109/ICET61945.2024.10673389(74-79)Online publication date: 17-May-2024
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      • (2023)Accurate Soft Error Rate Evaluation Using Event-Driven Dynamic Timing Analysis2023 IEEE International Symposium on Defect and Fault Tolerance in VLSI and Nanotechnology Systems (DFT)10.1109/DFT59622.2023.10313573(1-6)Online publication date: 3-Oct-2023
      • (2023)RC-GNN: Fast and Accurate Signoff Wire Delay Estimation with Customized Graph Neural Networks2023 IEEE 5th International Conference on Artificial Intelligence Circuits and Systems (AICAS)10.1109/AICAS57966.2023.10168562(1-5)Online publication date: 11-Jun-2023
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