Efficient scan chain insertion using broadcast scan for reduced bit collisions
US7441171B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 24, 2006 |
| Grant date | Oct 21, 2008 |
| Priority date | — |
| Expiry date | Apr 14, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/318544
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed is a method of inserting scan elements onto scan chains of broadcast scan structures to minimize the number of collisions in a plurality of logic cones. Each logic cone is selected and evaluated to identify all of the scan elements that provide inputs thereto. The identified scan elements are systematically inserted into the scan chains in the broadcast scan structure in a manner that minimizes insertion of multiple scan elements into the same sequential position on different scan chains that receive a test pattern from the same scan-in pin. If possible, the elements are inserted into the same scan chain or into scan chains that fan out from different pins. Optionally, if multiple elements are inserted at the same sequential position in scan chains that fan out from the same pin, these multiple elements can be marked so that they will not be used for test generation, thereby, completely eliminating bit collisions
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.