Determining the value of internal signals in a malfunctioning integrated circuit
US7493434B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | May 25, 2005 |
| Grant date | Feb 17, 2009 |
| Priority date | — |
| Expiry date | Aug 3, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/318533
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method that enables testing any point (target point) within a core, including a point within a combinatorial circuit of a core, permits testing of points that are not otherwise unobservable in normal debugging processes. Such a target point is tested by identifying a fanout cone from that point to observable outputs, and by performing one or more tests, where each test sensitizes one or more paths that extend the signal of the target point, or its complement, to one or more of the observable outputs, and ascertains the values at those observable outputs. By having more than one observable output at which the signal of target point (or its complement) is tested significantly increases the level of confidence in the test when the observable points concur in the signal value of the target point.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.