Robust paradigm for diagnosing hold-time faults in scan chains

2007 ◽  
Vol 1 (6) ◽  
pp. 706 ◽  
Author(s):  
C.-W. Tzeng ◽  
J.-J. Hsu ◽  
S.-Y. Huang
Keyword(s):  
Author(s):  
Yu Huang ◽  
Wu-Tung Cheng ◽  
Ting-Pu Tai ◽  
Liyang Lai ◽  
Ruifeng Guo ◽  
...  

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.


Author(s):  
Huaxing Tang ◽  
Allen Yang ◽  
Zhanjun Shu ◽  
Eden Cai ◽  
Shizhong Chen ◽  
...  

Abstract Scan-based test has been the industrial standard method for screening manufacturing defects. Scan chains are vulnerable to most manufacturing defects and process variations. Therefore, chain failures diagnosis is critical for successful yield learning. However, traditional chain diagnosis requires failing masking patterns to identify faulty chains and their fault types for designs with test compression. In other words, it cannot diagnose the chain failures which don't fail the masking chain patterns. Unfortunately, advanced FinFET technologies with more manufacturing challenges and higher process variations may result in more subtle chain timing failures which can't be detected by chain masking patterns. In this work, we present a new debugging methodology, which combines chain diagnosis and tester-based test to effectively diagnose such intermittent chain failures. The proposed methodology is validated on silicon data for one modern large SOC design and successfully identified all scan cells with hold-time issues, which were validated by STA with corrected models. The subsequent mask fixes for these identified hold-time violations resolved this yield issue and dramatically improve the yield.


2005 ◽  
Vol 54 (11) ◽  
pp. 1467-1472 ◽  
Author(s):  
J.C.-M. Li
Keyword(s):  

2020 ◽  
Vol 91 (7) ◽  
pp. 578-585
Author(s):  
Victory C. Madu ◽  
Heather Carnahan ◽  
Robert Brown ◽  
Kerri-Ann Ennis ◽  
Kaitlyn S. Tymko ◽  
...  

PURPOSE: This study was intended to determine the effect of skin cooling on breath-hold duration and predicted emergency air supply duration during immersion.METHODS: While wearing a helicopter transport suit with a dive mask, 12 subjects (29 ± 10 yr, 78 ± 14 kg, 177 ± 7 cm, 2 women) were studied in 8 and 20°C water. Subjects performed a maximum breath-hold, then breathed for 90 s (through a mouthpiece connected to room air) in five skin-exposure conditions. The first trial was out of water for Control (suit zipped, hood on, mask off). Four submersion conditions included exposure of the: Partial Face (hood and mask on); Face (hood on, mask off); Head (hood and mask off); and Whole Body (suit unzipped, hood and mask off).RESULTS: Decreasing temperature and increasing skin exposure reduced breath-hold time (to as low as 10 ± 4 s), generally increased minute ventilation (up to 40 ± 15 L · min−1), and decreased predicted endurance time (PET) of a 55-L helicopter underwater emergency breathing apparatus. In 8°C water, PET decreased from 2 min 39 s (Partial Face) to 1 min 11 s (Whole Body).CONCLUSION: The most significant factor increasing breath-hold and predicted survival time was zipping up the suit. Face masks and suit hoods increased thermal comfort. Therefore, wearing the suits zipped with hoods on and, if possible, donning the dive mask prior to crashing, may increase survivability. The results have important applications for the education and preparation of helicopter occupants. Thermal protective suits and dive masks should be provided.Madu VC, Carnahan H, Brown R, Ennis K-A, Tymko KS, Hurrie DMG, McDonald GK, Cornish SM, Giesbrecht GG. Skin cooling on breath-hold duration and predicted emergency air supply duration during immersion. Aerosp Med Hum Perform. 2020; 91(7):578–585.


Author(s):  
Ruifeng Guo ◽  
Srikanth Venkataraman

Abstract In this paper, we present a scan chain fault diagnosis procedure. The diagnosis for a single scan chain failure is performed in three steps. The first step uses special chain test patterns to determine both the faulty chain and the fault type in the faulty chain. The second step uses a novel procedure to generate special test patterns to identify the suspect scan cell within a range of scan cells. Unlike previously proposed methods that restrict the location of the faulty scan cell only from the scan chain output side, our method restricts the location of the faulty scan cell from both the scan chain output side and the scan chain input side. Hence the number of suspect scan cells is reduced significantly in this step. The final step further improves the diagnostic resolution by ranking the suspect scan cells inside this range. The proposed technique handles both stuck-at and timing failures (transition faults and hold time faults). The experimental results based on simulation and silicon units for several products show the effectiveness of the proposed method.


Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 307
Author(s):  
Matthias Bruchhausen ◽  
Gintautas Dundulis ◽  
Alec McLennan ◽  
Sergio Arrieta ◽  
Tim Austin ◽  
...  

A substantial amount of research effort has been applied to the field of environmentally assisted fatigue (EAF) due to the requirement to account for the EAF behaviour of metals for existing and new build nuclear power plants. We present the results of the European project INcreasing Safety in NPPs by Covering Gaps in Environmental Fatigue Assessment (INCEFA-PLUS), during which the sensitivities of strain range, environment, surface roughness, mean strain and hold times, as well as their interactions on the fatigue life of austenitic steels has been characterized. The project included a test campaign, during which more than 250 fatigue tests were performed. The tests did not reveal a significant effect of mean strain or hold time on fatigue life. An empirical model describing the fatigue life as a function of strain rate, environment and surface roughness is developed. There is evidence for statistically significant interaction effects between surface roughness and the environment, as well as between surface roughness and strain range. However, their impact on fatigue life is so small that they are not practically relevant and can in most cases be neglected. Reducing the environmental impact on fatigue life by modifying the temperature or strain rate leads to an increase of the fatigue life in agreement with predictions based on NUREG/CR-6909. A limited sub-programme on the sensitivity of hold times at elevated temperature at zero force conditions and at elevated temperature did not show the beneficial effect on fatigue life found in another study.


2015 ◽  
Vol 118 (24) ◽  
pp. 245904 ◽  
Author(s):  
S. Wong ◽  
B. Haberl ◽  
J. S. Williams ◽  
J. E. Bradby

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