Virtual scan chains: a means for reducing scan length in cores

Diagnose Compound Hold Time Faults Caused by Spot Delay Defects at Clock Tree

ISTFA 2011: Conference Proceedings from the 37th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2011p0103 ◽

2011 ◽

Author(s):

Yu Huang ◽

Wu-Tung Cheng ◽

Ting-Pu Tai ◽

Liyang Lai ◽

Ruifeng Guo ◽

...

Keyword(s):

Hold Time ◽

Clock Signal ◽

Clock Tree ◽

Scan Testing ◽

Design Error ◽

Functional Logic ◽

Scan Chains ◽

Delay Defects

Abstract If a signal on clock tree is slower than expected due to either a design error or a manufacturing defect, it may cause complicated fault behaviors during scan-based testing. It makes the diagnosis of such defect especially difficult if the defective clock signal is used for both shift and capture operations during the scan testing, because (1) the defect induces hold time faults on scan chains during shift cycles, and (2) hold-time faults may also be introduced during capture cycles in the functional logic paths. In this paper we illustrate the failure behaviors of such clock defects and propose an algorithm to diagnose it.

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An algorithmic technique for diagnosis of faulty scan chains

IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems ◽

10.1109/tcad.2005.858267 ◽

2006 ◽

Vol 25 (9) ◽

pp. 1861-1868 ◽

Cited By ~ 21

Author(s):

Ruifeng Guo ◽

S. Venkataraman

Keyword(s):

Scan Chains ◽

Algorithmic Technique

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The Effect of General Anesthesia On Test-Retest Reliability of Resting-State FMRI Metrics And Optimization of Scan Length

10.21203/rs.3.rs-992129/v1 ◽

2021 ◽

Author(s):

Faezeh Vedaei ◽

Mahdi Alizadeh ◽

Victor M Romo ◽

Feroze B. Mohamed ◽

Chengyuan Wu

Keyword(s):

Resting State ◽

Intraclass Correlation ◽

Resting State Fmri ◽

Frequency Fluctuation ◽

Retest Reliability ◽

Factors Affecting ◽

Fractional Frequency ◽

Drug Resistant Epilepsy ◽

Test Retest Reliability ◽

Scan Length

Abstract Resting-state functional magnetic resonance imaging (rs-fMRI) has been known as a powerful tool in neuroscience. However, exploring the test-retest reliability of the metrics derived from rs-fMRI BOLD signal is essential particularly in the studies of patients with neurological development. Two factors affecting reliability of rs-fMRI measurements including the effect of anesthesia and scan length have been estimated in this study. A total of 9 patients with drug-resistant epilepsy (DRE) of requiring interstitial thermal therapy (LITT) were scanned in two states of awake and under anesthesia. At each state, two rs-fMRI sessions were obtained that each one lasted 15 minutes, and the effect of scan length was evaluated. Voxel-wise rs-fMRI metrics including amplitude of low fractional frequency fluctuation (ALFF), amplitude of low fractional frequency fluctuation (fALFF), functional connectivity (FC), and regional homogeneity (ReHo) were measured. Intraclass correlation coefficient (ICC) was calculated to estimate the reliability between two sessions of scanning for both states. Overall, our finding revealed that reliability improves under anesthesia as well as by increasing the scanning length of the scanning sessions. Furthermore, we showed that the optimal scan length to achieve reliable rs-fMRI measurements was 3.1 – 7.5 minutes shorter in an anesthetized, compared to wakeful state.

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