The document summarizes a seminar presentation on fault simulation techniques. It discusses (1) different fault simulation methods like serial, parallel, and concurrent fault simulation, (2) how concurrent fault simulation works using an example circuit, and (3) applications of fault simulation like measuring fault coverage, generating test vectors, and creating fault dictionaries. The presentation concludes with references for further reading on fault simulation and testing techniques.
Level sensitive scan design(LSSD) and Boundry scan(BS)Praveen Kumar
This presentation contains,
Introduction,design for testability, scan chain, operation, scan structure, test vectors, Boundry scan, test logic, operation, BS cell, states of TAP controller, Boundry scan instructions.
IMPLEMENTATION AND VALIDATION OF MEMORY BUILT IN SELF TEST (MBIST) - SURVEYIAEME Publication
This paper provides a survey of Implementation and Validation involved in Memory Built in Self-Test (MBIST). This paper comprises of the various strategies involved in the implementation and Validation of the Memory Built in Self-Test (MBIST). MBIST (Memory built-in self-test) provides an effective solution for testing of such large memories. Verification of functioning MBIST is an essential part in any SoC design cycle, as it enables the designer to detect beforehand any issues related to MBIST [11] . The advantages of MBIST are simplicity of test program, Possibility to run different algorithm, Reduction in test cost, Possibility to run user defined algorithm on memories.
Level sensitive scan design(LSSD) and Boundry scan(BS)Praveen Kumar
This presentation contains,
Introduction,design for testability, scan chain, operation, scan structure, test vectors, Boundry scan, test logic, operation, BS cell, states of TAP controller, Boundry scan instructions.
IMPLEMENTATION AND VALIDATION OF MEMORY BUILT IN SELF TEST (MBIST) - SURVEYIAEME Publication
This paper provides a survey of Implementation and Validation involved in Memory Built in Self-Test (MBIST). This paper comprises of the various strategies involved in the implementation and Validation of the Memory Built in Self-Test (MBIST). MBIST (Memory built-in self-test) provides an effective solution for testing of such large memories. Verification of functioning MBIST is an essential part in any SoC design cycle, as it enables the designer to detect beforehand any issues related to MBIST [11] . The advantages of MBIST are simplicity of test program, Possibility to run different algorithm, Reduction in test cost, Possibility to run user defined algorithm on memories.
Scan design is currently the most popular structured DFT approach. It is implemented by Connecting selected storage elements present in the design into multiple shift registers, called Scan chains.
Scannability Rules -->
The tool perform basic two check
1) It ensures all the defined clocks including set/Reset are at their off-states, the sequential element remain stable and inactive. (S1)
2) It ensures for each defined clocks can capture data when all other defined clocks are off. (S2)
UVM is a standardized methodology for verifying complex IP and SOC in the semiconductor industry. UVM is an Accellera standard and developed with support from multiple vendors Aldec, Cadence, Mentor, and Synopsys. UVM 1.0 was released on 28 Feb 2011 which is widely accepted by verification Engineer across the world. UVM has evolved and undergone a series of minor releases, which introduced new features.
UVM provides the standard structure for creating test-bench and UVCs. The following features are provided by UVM
• Separation of tests from test bench
• Transaction-level communication (TLM)
• Sequences
• Factory and configuration
• Message reporting
• End-of-test mechanism
• Register layer
Introduction of testing and verification of vlsi designUsha Mehta
This slides are introductory slides for the course testing and verification of VLSI Design which cover the basics of Why, Where, When and How of VLSI design testing
Spyglass DFT is comprehensive process of resolving RTL Design issues, thereby ensuring high quality RTL with fewer design bugs.
Improves test quality by diagnosing DFT issues early at RTL or netlist.
Shortens test implementation time and cost by ensuring RTL or netlist is scan-compliant.
Scan design is currently the most popular structured DFT approach. It is implemented by Connecting selected storage elements present in the design into multiple shift registers, called Scan chains.
Scannability Rules -->
The tool perform basic two check
1) It ensures all the defined clocks including set/Reset are at their off-states, the sequential element remain stable and inactive. (S1)
2) It ensures for each defined clocks can capture data when all other defined clocks are off. (S2)
UVM is a standardized methodology for verifying complex IP and SOC in the semiconductor industry. UVM is an Accellera standard and developed with support from multiple vendors Aldec, Cadence, Mentor, and Synopsys. UVM 1.0 was released on 28 Feb 2011 which is widely accepted by verification Engineer across the world. UVM has evolved and undergone a series of minor releases, which introduced new features.
UVM provides the standard structure for creating test-bench and UVCs. The following features are provided by UVM
• Separation of tests from test bench
• Transaction-level communication (TLM)
• Sequences
• Factory and configuration
• Message reporting
• End-of-test mechanism
• Register layer
Introduction of testing and verification of vlsi designUsha Mehta
This slides are introductory slides for the course testing and verification of VLSI Design which cover the basics of Why, Where, When and How of VLSI design testing
Spyglass DFT is comprehensive process of resolving RTL Design issues, thereby ensuring high quality RTL with fewer design bugs.
Improves test quality by diagnosing DFT issues early at RTL or netlist.
Shortens test implementation time and cost by ensuring RTL or netlist is scan-compliant.
Automatic test packet generation in networkeSAT Journals
Abstract Now a day’s we see that networks are widely distributed so administrators depends on various tools such as ping and traceroute to rectify the problem in the network. We proposed an automated and systematic approach for testing and debugging network called "Automatic Test Packet Generation"(ATPG). Initially ATPG reads router configuration and then generates a model which is device freelance. The model is used to generate the minimum number of test packets to cover every link and rule in network. ATPG is capable for detecting both functional and performance problems. Test packets are sent at regular intervals and special technique is used to localize faults. Keywords: Test Packet Generation Algorithm; Network Troubleshooting; Data Plane Analysis.
EVOLUTION OF VOLTAGE REGULATOR TO SYSTEM ON CHIP APPLICATIONSIAEME Publication
People demanding for smaller hand-held devices is increasing because of the growing applications within these portable System on Chip (SoC) applications, such as cellular phones, tabs, laptops, etc... Consequently industry is also pushing towards miniaturization. New technologies are emerging to make device smaller and smaller, by decreasing transistor length only to few nano-meters. During the journey of miniaturization, voltage regulator is being a key factor of discussion for SoC applications from many years. Researchers have been working constantly to formulate a design for voltage regulators. Many compensation methods have been emerging from last two decades to overcome problems associated with precursor technique. This paper insights the pathway which leads to development of Capacitor-Less Low Drop out (CL-LDO) Voltage Regulator, since CL-LDO architecture is the most suitable architecture for System on Chip applications.
Dynamic Simulation for HFE & Control System Design ValidationGSE Systems, Inc.
This presentation explains how dynamic simulation can be used for human factors engineering and for control system design validation.
Digital instrumentation and control (I&C) and digital control rooms have become a key focus of the nuclear industry. Regulator must understand and validate these system designs and their performance in order to budget and schedule risk, and for safety.
For more information, go to www.GSES.com, email info@gses.com, and follow us on Twitter @GSESystems and Facebook.com/gsesystems. Thank for viewing!
Wavelet Based on the Finding of Hard and Soft Faults in Analog and Digital Si...ijcisjournal
In this paper methods for testing both software and hardware faults are implemented in analog and digital
signal circuits are presented. They are based on the wavelet transform (WT). The limit which affected by
faults detect ability, for the reference circuits is set by statistical processing data obtained from a set of
faults free circuits .In wavelet analysis it has two algorithm one is based on a discrimination factor using
Euclidean distances and the other mahalanobis distances, are introduced both methods on wavelet energy
calculation. Simulation result from proposed test methods in the testing known analog and digital signal
circuit benchmark are given. The results shows that effectiveness of existing methods two test metrics
against three other test methods, namely a test method based on rms value of the measured signal, a test
method utilizing the harmonic magnitude component of the measured signal waveform
Fault Modeling for Verilog Register Transfer Levelidescitation
As the complexity of Very Large Scale Integration
(VLSI) increases, testing becomes tedious. Currently fault
models are used to test digital circuits at gate level or at levels
lower than gate. Modeling faults at these levels, leads to
increase in the design cycle time period. Hence, there is a
need to explore new approaches for modeling faults at higher
levels. This paper proposes fault modeling at the Register
Transfer Level (RTL) for digital circuits. Using this level of
modeling, results are obtained for fault coverage, area and
test patterns. A software prototype, FEVER, has been developed
in C which reads a RTL description and generates two output
files: one a modified RTL with test features and two a file
consisting of set of test patterns. These modified RTL and test
patterns are further used for fault simulation and fault
coverage analysis. Comparison is performed between the RTL
and Gate level modeling for ISCAS benchmarks and the
results of the same are presented. Results are obtained using
Synopsys, TetraMax and it is shown that it is possible to achieve
100% fault coverage with no area overhead at the RTL level
IMPLEMENTATION OF COMPACTION ALGORITHM FOR ATPG GENERATED PARTIALLY SPECIFIED...VLSICS Design
In this paper the ATPG is implemented using C++. This ATPG is based on fault equivalence concept in which the number of faults gets reduced before compaction method. This ATPG uses the line justification and error propagation to find the test vectors for reduced fault set with the aid of controllability and observability. Single stuck at fault model is considered. The programs are developed for fault equivalence method, controllability Observability, automatic test pattern generation and test data compaction using object oriented language C++. ISCAS 85 C17 circuit was used for analysis purpose along with other circuits. Standard ISCAS (International Symposium on Circuits And Systems) netlist format was used. The flow charts and results for ISCAS 85 C17 circuits along with other netlists are given in this paper. The test vectors generated by the ATPG further compacted to reduce the test vector data. The algorithm is developed for the test vector compaction and discussed along with results.
The Application Fault Tolerance (AFT) portion of the Jet Propulsion Laboratory-led Remote Exploration and Experimentation (REE) final review, May 2001, with references to REE-produced AFT papers added after the review (last three slides)
Software Reliability Growth Model with Logistic- Exponential Testing-Effort F...IDES Editor
Software reliability is one of the important factors of
software quality. Before software delivered in to market it is
thoroughly checked and errors are removed. Every software
industry wants to develop software that should be error free.
Software reliability growth models are helping the software
industries to develop software which is error free and reliable.
In this paper an analysis is done based on incorporating the
logistic-exponential testing-effort in to NHPP Software
reliability growth model and also observed its release policy.
Experiments are performed on the real datasets. Parameters
are calculated and observed that our model is best fitted for
the datasets.
Heuristic approach to optimize the number of test cases for simple circuitsVLSICS Design
In this paper a new solution is proposed for testing simple stwo stage electronic circuits. It minimizes the number of tests to be performed to determine the genuinity of the circuit. The main idea behind the present research work is to identify the maximum number of indistinguishable faults present in the given circuit and minimize the number of test cases based on the number of faults that has been detected. Heuristic approach is used for test minimization part, which identifies the essential tests from overall test cases. From the results it is observed that, test minimization varies from 50% to 99% with the lowest one corresponding to a circuit with four gates .Test minimization is low in case of circuits with lesser input leads in gates compared to greater input leads in gates for the boolean expression with same number of symbols. Achievement of 99% reduction is due to the fact that the large number of tests find the same faults. The new approach is implemented for simple circuits. The results show potential for both smaller test sets and lower cpu times.
Heuristic approach to optimize the number of test cases for simple circuitsVLSICS Design
In this paper a new solution is proposed for testing simple stwo stage electronic circuits. It minimizes the number of tests to be performed to determine the genuinity of the circuit. The main idea behind the present research work is to identify the maximum number of indistinguishable faults present in the given circuit and minimize the number of test cases based on the number of faults that has been detected. Heuristic approach is used for test minimization part, which identifies the essential tests from overall test cases. From the results it is observed that, test minimization varies from 50% to 99% with the lowest one corresponding to a circuit with four gates .Test minimization is low in case of circuits with lesser input leads in gates compared to greater input leads in gates for the boolean expression with same number of symbols. Achievement of 99% reduction is due to the fact that the large number of tests find the same faults. The new approach is implemented for simple circuits. The results show potential for both smaller test sets and lower cpu times.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
2024.06.01 Introducing a competency framework for languag learning materials ...
Fault simulation – application and methods
1. Seminar
Fault Simulation – Application and Methods
Subash John
CGB0911005
VSD 530
M.Sc. [Engg.] in VLSI System Design
Module Title: Reliable Power Aware ASICs
Module Leader: Mr. Padmanaban K.
M. S. Ramaiah School of Advanced Studies 1
2. Contents
• Introduction
• Fault simulation environment
• Fault simulation methods
• Concurrent fault simulation illustration
• Fault simulation applications
• Conclusion
• References
M. S. Ramaiah School of Advanced Studies 2
3. Introduction
• Fault simulation consists of simulating a circuit in the presence of faults
• To test an ASIC, a series of inputs patterns are required that will detect any
faults
• There are several algorithms for fault simulation: serial fault
simulation, parallel fault simulation, concurrent fault simulation and deductive
fault simulation
• Any algorithm consists of 5 specific tasks:
• Fault free circuit simulation
• Fault specification
• Fault insertion (fault list generation and collapsing)
• Fault-effect generation and propagation
• Fault detection and discarding
M. S. Ramaiah School of Advanced Studies 3
4. Fault simulation environment
Test Data
Test Application
Golden Model
Data Response Comparison
Report generation Reports
Fault Test data Validation
Fault able Model
List Fault
Injection
Figure 1. Fault Simulation process [1]
M. S. Ramaiah School of Advanced Studies 4
5. Fault Simulation Methods (1/2)
Serial fault simulation
• Fault free circuit is simulated first and the results are stored in a file
• Next, faulty circuits are simulated one by one
• The output values of the faulty circuit are dynamically compared with the saved fault-
free responses
• For n faults, the CPU time of a serial simulator can be almost n times that of a fault-free
simulator
Parallel fault simulation
• Performed using bitwise logic operations
• Takes advantage of parallelism inherent in host computer to reduce fault simulation time
• A fault is detected if its bit value differs from that of the fault-free circuit at any of the
outputs
• Parallel fault simulation technique is applicable to the unit or zero delay models only
M. S. Ramaiah School of Advanced Studies 5
6. Fault Simulation Methods (2/2)
Concurrent fault simulation
• Parallel fault simulation requires multiple parallel circuits resulting in large
memories and long simulation times
• In concurrent simulation only gates which propagate the faults are duplicated
and simulated, thus saving processing time
Algorithm for concurrent fault simulation
Given test T, n test vectors, t1:n;
Given fault list F, m faults, f1:m; f0 no fault;
Consider all faults for concurrent injection
For i in 1 to n Loop – every t in T
Propagate t1;
If due to fault fj a gate output is faulty
Duplicate gate with faulty output
End if;
End for;
M. S. Ramaiah School of Advanced Studies 6
7. Concurrent fault simulation illustration (1/3)
• Assume that A: ST - 1, C: ST – 0, J: ST – 0.
Table 1. Test for stuck at one fault at node A
Step A B C E=F=L J H K
Initial 0 1 0 1 0 0 1
Faulty 1 1 0 1 0 1 0
M. S. Ramaiah School of Advanced Studies 7
8. Concurrent fault simulation illustration (2/3)
Table 2. Test for stuck at zero fault at node C
Step A B C E=F=L J H K
Initial 0 0 1 1 0 0 1
Faulty 0 0 0 0 1 0 0
M. S. Ramaiah School of Advanced Studies 8
9. Concurrent fault simulation illustration (3/3)
Table 3. Test for stuck at zero fault at node J
Step A B C E=F=L J H K
Initial 1 0 0 0 1 0 0
Faulty 1 0 0 0 1 0 0 1
M. S. Ramaiah School of Advanced Studies 9
10. Fault simulation applications (1/3)
1. Fault coverage (test coverage)
• Ratio of detected faults over total faults in a circuit
Algorithm for concurrent fault coverage Table 4. Fault Coverage [2]
Given Test Set T, n test vectors, t1:n;
Fault Average Repair
Given Fault List F, m faults, f1:m;f0 no fault;
Coverage Defect Cost
For j in 1 to m loop -- every f in F
Level
Inject fj;
For i in 1 to n loop -- every t in T 50% 7% $2Million
While fj is not detected begin 90% 3% $200,000
Simulate faulty circuit;
95% 1% $20,000
Increment DF if fj is detected;
End while; 99% 0.1% $2,000
End for; 99.9% 0.01% $200
Remove fj;
End for;
Record DF, detected fault in F;
Calculate %FC based on m and DF;
Fault coverage = m/DF
M. S. Ramaiah School of Advanced Studies 10
11. Fault simulation applications (2/3)
2. Test generation
• Process of obtaining test vectors for detecting circuit faults
(1) Test refinement
• Test efficiency is the number of faults covered by a test vector
• Test vectors that are low in efficiency, or test vectors that detect faults
already covered by other test vectors can be removed from the test set
• As such, a test set can be refined for the fewest number of tests and the
highest coverage
(2) Random test generation
• Can be regarded as a replacement for costly ATPG algorithms
• By fault simulation, a randomly generated input vector is examined for
detection of faults, and based on this, it is decided whether to keep the
vector as a test vector or to drop it
M. S. Ramaiah School of Advanced Studies 11
12. Fault simulation applications (3/3)
3. Fault Dictionary
• Consists of simulated responses for all faults in fault list, stored in database
• Used by some diagnosis algorithms for convenience:
– Fast: No simulation at time of diagnosis
– Self-contained: net list, simulator, and test set not needed after dictionary
creation
Table 5. Multiplexer fault dictionary [1]
M. S. Ramaiah School of Advanced Studies 12
13. Summary
• Major concerns of fault simulation techniques are the simulation speed and the
required memory
• It is apparent that serial fault simulation is the slowest among all the
techniques
• From the aspect of delay and functional modeling capability, serial fault
simulation does not encounter any difficulty.
• Parallel fault simulation cannot take delay or functional models into account as
they pack the information of multiple faults or test patterns into the same word
and rely on bitwise logic operations
• Being event driven, concurrent fault simulation techniques are capable of
handling functional models
M. S. Ramaiah School of Advanced Studies 13
14. References
[1] Bushnell and Agrawal (2002) Essentials of Electronic Testing for Digital,
Memory and Mixed-Signal VLSI Circuits. New York: Kluwer Academic
Publishers
[2] Wang, Wu and Wen (2006) VLSI Test Principles and Architectures: Design
for Testability. San Francisco: Morgan Kaufmann Publishers
[3] Zainalabedin Navabi (2011) Digital System Test and Testable Design. New
York: Springer
M. S. Ramaiah School of Advanced Studies 14
16. Remarks
Sl. No. Topic Max. marks Marks
obtained
1 Quality of slides 5
2 Clarity of subject 5
3 Presentation 5
4 Effort and question handling 5
Total 20
M. S. Ramaiah School of Advanced Studies 16