Method and apparatus for diagnosing broken scan chain based on leakage light emission
Patent 7426448 Issued on September 16, 2008. Estimated Expiration Date: 
February 3, 2024. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
February 3, 2024. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesScan structure for improving transition fault coverage and scan diagnostics Stuck-at fault scan chain diagnostic method Patent #: 7010735 InventorsAssigneeApplicationNo. 10771218 filed on 02/03/2004US Classes:702/117, Of circuit712/16Array processor operationExaminersPrimary: Raymond, EdwardAttorney, Agent or FirmInternational ClassG06F 19/00AbstractA mechanism for diagnosing broken scan chains based on leakage light emission is provided. An image capture mechanism detects light emission from leakage current in complementary metal oxide semiconductor (CMOS) devices. The diagnosis mechanism identifies devices with unexpected light emission. An unexpected amount of light emission may indicate that a transistor is turned off when it should be turned on or vice versa. All possible inputs may be tested to determine whether a problem exists with transistors in latches or with transistors in clock buffers. Broken points in the scan chain may then be determined based on the locations of unexpected light emission. | |
