Weibull Based Analytical Waveform Model

ABSTRACT

Current CMOS technologies are characterized by interconnectlines with increased relative resistance w.r.t. driver outputresistance. Designs generate signal waveshapes that are verydifficult to model using a single parameter model such as thetransition time. In this paper, we present a simple and robustparameter analytical expression for waveform modeling based onthe Weibull cumulative distribution function. The Weibull modelaccurately captures the variety of waveshapes without introducingsignificant runtime overhead and produces results with less than5% error. We also present a fast and simple algorithm to convertwaveforms obtained by circuit simulation to the Weibull model. Amethodology for characterizing gates for the new model is alsopresented. Simulation results for many single and multiple inputgates show errors well below 5%. Our model can be used in amixed environment where some signals may still be characterizedby a single parameter.

REFERENCES

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.4 INPUT/OUTPUT AND DATA COMMUNICATIONS
      B.4.3 Interconnections (subsystems)
          Subjects: Topology (e.g., bus, point-to-point)

Additional Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.1 Types and Design Styles
          Subjects: Gate arrays

  I. Computing Methodologies
  I.5 PATTERN RECOGNITION
      I.5.4 Applications
          Subjects: Waveform analysis

General Terms:
Algorithms, Design, Performance