Patent · US Expired

Systems and methods for LBIST testing using multiple functional subphases

US7308634B2 · kind B2 · utility

7Cited by
7References
16Claims
0Family size

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Key dates

Filing dateApr 1, 2005
Grant dateDec 11, 2007
Priority date
Expiry dateNov 2, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/318536
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Systems and methods for performing logic built-in-self-tests (LBISTs) in digital circuits, where the LBIST circuitry is configured to propagate data through different portions of the functional logic of the circuits at different times. In one embodiment, a logic circuit incorporates LBIST components including a set of scan chains interposed between portions of the functional logic. Pseudorandom bit patterns are scanned into the scan chains so that they can be propagated through the functional logic following the scan chains. The resulting bit patterns are captured in scan chains following the functional logic and then scanned out of these scan chains. An LBIST controller causes functional operations in different portions of the functional logic to be performed at different times during a functional phase of a test cycle. The functional operations may be performed at a normal operating speed, while scan shift operations may be performed at a lower speed.

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