Method and apparatus for implementing enhanced LBIST diagnostics of intermittent failures
US6807645B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 4, 2002 |
| Grant date | Oct 19, 2004 |
| Priority date | — |
| Expiry date | Apr 26, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/31813
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus are provided for enhanced Logic Built in Self Test (LBIST) diagnostics. First multiplexers are respectively coupled between adjacent sequential channels of a plurality of sequential channels under test. Each of the first multiplexers selectively receives a first data input in a first scan mode with the sequential channels configured in a common scan path and a second data input in a second scan mode with each the sequential channels configured in a separate scan path responsive to a first control signal. A first multiple input signature register (MISR) including multiple MISR inputs is coupled to a respective one of the plurality of sequential channels under test. A blocker function is configured for blocking all MISR inputs except for a single MISR input receiving the test data output of the last sequential channel responsive to a recirculate control signal. A second MISR shadow register is coupled to the first multiple input signature register.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.