Scan stream sequencing for testing integrated circuits
US6748564B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2000 |
| Grant date | Jun 8, 2004 |
| Priority date | — |
| Expiry date | Jan 5, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C29/56
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system and method for processing scan data for integrated circuit testing. Scan data is divided into three groups of scan data segments: scan-in data segments, scan-out data segments and scan-mask data segments. The sequence of scan data segments in each group constitutes the operative test data in a scan stream. Each scan stream is represented by a table having a row corresponding to each scan data segment in the stream. Each row has four fields: a start address, a segment length, a start pad length and an end pad length. The start address is a pointer to the scan data segment in memory where the scan data segment is stored in a contiguous portion of memory. Scan data segment length is the length in bits of the segment. Start pad length is a delay value measured in number of scan clock cycles that must elapse before processing the respective segment in the scan stream. End pad length is a delay value measured in number of scan clock cycles that must elapse before processing the next start pad length and scan data segment in the scan stream. Scan streams consist of the bit sequence of segment data interposed by dummy data corresponding in length to the start pad and end pad lengt…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.