Patent · US Expired

Hybrid linear wire model approach to tuning transistor widths of circuits with RC interconnect

US7325210B2 · kind B2 · utility

10Cited by
13References
13Claims
0Family size

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Key dates

Filing dateMar 10, 2005
Grant dateJan 29, 2008
Priority date
Expiry dateMar 10, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2119/12
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A hybrid linear wire model for tuning the transistor widths of circuits linked by RC interconnects is described. The method uses two embedded simulators during the tuning process on netlists that contain resistors (Rs). A Timing oriented simulator is used only for timing purposes on the original netlist that includes all the Rs. A Gradient oriented simulator is then run only on the modified netlist with all Rs shorted and within the iterative loop of the tuner to compute gradients. The present hybrid method achieves a significant improvement in computational speed. The Timing oriented simulator is fast and accurate for only timing netlists with Rs, but cannot compute gradients efficiently. The Gradient oriented simulator computes gradients efficiently but cannot do so in the presence of Rs. To prevent “de-tuning” that typically occurs when all Rs are shorted, ‘wire-adjusts’ are provided that make the initial timing results using the Gradient oriented simulator on the shorted netlist match the timing results using Timing oriented simulator on the original netlist. This permits the optimizer sense initially the correct set of critical timing paths, and more significantly, it permits …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.