Diagnosable scan chain

US7007214B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Steven M. Eustis · South Burlington, US
• Leah Pastel · Saint Johnsbury Center, US
• Thomas R. Bednar · Pewaukee, US
• Thomas G. Sopchak · Williston, US
• Jeffery H. Oppold · South Burlington, US

Key dates

• Filing date: Jun 30, 2003
• Grant date: Feb 28, 2006
• Expiry date: Aug 25, 2024

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R31/31855
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method and system for locating connector defects in a defective scan chain that has a parallel non-defective scan chain on a different wiring level, with both scan chains being laid out in a regular array pattern. A predetermined bit sequence is scanned into the defective scan chain. The contents of the defective scan chain are then parallel shifted into the non-defective scan chain. The contents of the non-defective scan chain is then scanned out and compared with the predetermined bit sequence. The comparison of the scanned out bits with the predetermined bit sequence facilitates locating both physically and logically where a connector defect has occurred in the defective scan chain.