Patent · US Expired

Fast error diagnosis for combinational verification

US6662323B1 · kind B1 · utility

7Cited by
8References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 25, 1999
Grant dateDec 9, 2003
Priority date
Expiry dateOct 25, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/318502
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A fast error diagnosis system and process for combinational verification is described. The system and process localizes error sites in a combinational circuit implementation that has been shown to be inequivalent to its specification. In the typical case, it is not possible to identify the error location exactly. The invention uses a diagnosis strategy of gradually increasing the level of detail in the analysis algorithm to ultimately derive a small list of potential error sites in a short time. The invention combines the use of simulation, Binary Decision Diagrams, and Boolean satisfiability in a novel way to achieve the goal. The previous approaches have been limited in that they have either been constrained to a specific error model unlike the present invention, or they are inefficient in comparison to the present invention. The present invention allows for the final set of error sites derived to be small, where that set contains the actual error sites, and is derived in a reasonable amount of time.

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