Diagnosis by uut reduction fault diagnosis for combinational circuits selfchecking design system level diagnosis. Oct 18, 2014 vl7301 testing of vlsi circuits unit i testing and fault modelling introduction to testing faults in digital circuits modelling of faults logical fault models fault detection fault location fault dominance logic simulation types of simulation delay models gate level event driven simulation. It is notable that diagnosis is an inherently di cult. Diagnostic fault simulation of sequential circuits. Compaction of passfailbased diagnostic test vectors for. Fault detection in sequential circuits through functional testing ieee.
A genetic algorithm based two phase fault simulator for. Algorithms to locate multiple design errors using regionbased model are studied for both combinational and sequential circuits. It is shown that the use of multiple observation times has the potential of significantly enhancing the resolution of a given test set. Test pattern generation for sequential circuits on single stuckat fault model. Pdf a dynamic diagnosis scheme for synchronous sequential circuits is proposed. Fault diagnosis for analog circuits by using eemd, relative. Dynamic fault diagnosis of combinational and sequential. This method allows designers to perform dynamic fault location of stuckat faults in large.
Logical level diagnosis diagnosis by uut reduction fault diagnosis for combinational circuits selfchecking design system level diagnosis. Fault diagnosis in sequential circuits sciencedirect. Faults are defined and classified, the problems of detection and. Experimental results on iscas89 benchmark circuits are presented to demonstrate its capability. In this course material we design and analyze only synchronous sequential logic. Yet, the compaction of test vectors for fault diagnosis is little explored. Apr 15, 2020 basic concept of fault detection and location in sequential circuits notes edurev is made by best teachers of. Consequently the output is solely a function of the current inputs. This paper is concerned with the diagnosis of faults in synchronous sequential machines. Under certain conditions, one of them assuming nominal values for the circuit parameters, it was shown that only two measurements taken on two selected circuit nodes, at a single frequency, were needed to detect and diagnose any parametric fault. Us5515384a method and system of fault diagnosis of.
This paper presents a novel satbased solution for logic diagnosis of multiple faults or design errors in combinational and sequential circuits 18, 19. Different techniques have been proposed for stuckat fault diagnosis in combinational as well as sequential circuits. Diagnosis algorithms for integrated circuits ics are typically developed. Smith et al fault diagnosis and logic debugging using boolean satisfiability 1607 fig. Examples for sequential digital circuits are registers, shift register, counters etc.
A diagnostic fault simulator has been used to nd pairs of indistinguishable faults in combinational cir cuits for a given test set 1. We show that the test generation problem for all single stuckat faults in sequential circuits with internally balanced structures can be reduced into the. Sep, 2007 this article describes an emulationbased method for locating stuckat faults in combinational and synchronous sequential circuits. Automated test pattern generation for sequential circuits on single stuckat fault model. Pdf a fault detection method for combinational circuits. Delay fault diagnosis in sequential circuits request pdf. Modelbased fault diagnosis of sequential circuits and its acceleration. Fault diagnosis in synchronous sequential circuits based on an. Functional fault equivalence and diagnostic test generation in combinational logic circuits using conventional atpg andreas veneris1. Abadir3 sep seyedi1 abstract fault equivalence is an essential concept in digital design with signi. A number of heuristics are presented that keep the method.
A definition of passfail diagnosis suitable for the multiple observation times approach is also given. Hughes, virgil willis, fault diagnosis of sequential circuits 1969. Download fulltext pdf on improving fault diagnosis for synchronous sequential circuits conference paper pdf available july 1994 with 25 reads. The compaction of diagnostic test vectors must take care of all fault pairs that need to be distinguished by a given test vector set. Input signals change one at a time and only when the circuit is in the stable state. Pdf dynamic diagnosis of sequential circuits based on stuckat. Sample of the study material part of chapter 5 combinational. As a result, the capability of automatic test pattern generation atpg tool is improved for diagnosis of path delay faults. Diagnostic test pattern generation for sequential circuits. First, nominal and faulty response waveforms of a circuit are measured, respectively, and then are decomposed into intrinsic mode functions imfs with the eemd method. Fault detection in logical circuits by samprakash majumdar, b. A tool for singlefault diagnosis in linear analog circuits.
Pdf on improving fault diagnosis for synchronous sequential. Sequential circuits with combinational test generation complexity. Me vlsi design materials,books and free paper download. On improving fault diagnosis for synchronous sequential circuits. General terms sequential circuit, flip flop, algorithms et. Elec 326 1 sequential circuit analysis sequential circuit analysis objectives this section introduces synchronous sequential circuits with the following goals. Block diagram flip flop flip flop is a sequential circuit which generally samples its inputs and changes its outputs only at. The use of feedback in a device can introduce problems which are not found in strictly combinational circuits. Pdf diagnostic fault simulation of sequential circuits.
Modelbased fault diagnosis of sequential circuits and its. Fault diagnosis and logic debugging using boolean satisfiability. For fault detection, the test which detects the most faults which have not yet been detected, is the best choice. While a combinational circuit is a function of present input only. Sinceinmostapplicationsofthe decision tree thefinal conclusionwill bethatthenetworkis fail 2 reducing the computation time needed for gener. This document is highly rated by students and has been viewed 3462 times. This invention relates to the architecture, fault detection and diagnostic capabilities of a sequential control circuit, or sequencer. Fault detection in linear sequential circuits by aleksa petrovic a thesis submitted in partial fulfillment of the requirements for the degree of master of science in electrical engineering thesis directors signature. With the development of largescale integrated circuits, analog circuit complexity and the intensity increasing, the reliability requirements of the analog circuit are also stricter 1. Different types of sequential circuits basics and truth table.
Us3812337a sequential control circuit having improved fault. Diagnostic test generation for path delay faults in a scan. Download fault detection in digital circuits by arthur d. A fault detection method for combinational circuits. Since both problems have similar goals, we describe this work in terms of fault diagnosis unless otherwise stated.
The authors present a new functional test pattern generation algorithm for sequential architectures based on their finite state machine specification. Traditional single stuckat fault diagnosis usually involves the use of a fullresponse fault dictionary. Starting right from the basics, the authors take the reader through automatic test pattern generation, design for testability and built in selftest of digital circuits before moving on to more advanced topics such as iddq testing, functional testing, delay fault testing, memory testing, and fault diagnosis. Black box delay fault models for nonscan sequential circuits.
Sequential circuit analysis university of pittsburgh. A nand model for fault diagnosis in combinational logic network, sequence. Fault detection and test minimization methods for combinational circuits a survey. Fault diagnosis and logic debugging using boolean satis. But sequential circuit has memory so output can vary based on input.
Therefore, analog circuit testing and fault diagnosis problem cannot be avoided, thus it is important to carry out research on related theories and methods. This type of circuits uses previous input, output, clock and a memory element. Jul 19, 2015 apr 15, 2020 basic concept of fault detection and location in sequential circuits notes edurev is made by best teachers of. Give a precise definition of synchronous sequential circuits. Functional fault equivalence and diagnostic test generation. Therefore, the functional test generation methods based on circuit. Digital electronics part i combinational and sequential logic. Digital systems testing testable design download ebook pdf. Basic concept of fault detection and location in sequential. Pdf fault detection and test minimization methods for. A thesis in electrical engineering submitted to the graduate faculty of texas tech university in partial fulfillment of the requirements for the degree of master of science in electrical engineering approved c accepted may, 1975.
Faults are defined and classified, the problems of detection and diagnosis are discussed, and a previously presented algorithm for fault detection is outlined. Keywords genetic algorithm, sequential circuits, automatic test pattern generator, fault coverage, circuit under test, flipflop 1. Dudam2 amit kumar sinha3 1,2,3department of vlsi design 1,3vel tech university, chennai, india 2pune institute of computer technology, pune abstractin any circuit that comprises the logic gates. Electronic testing and fault diagnosis 3rd edition. The method is based on automatically designing a circuit which implements a closestmatch fault location algorithm specialized for the circuit under diagnosis cud. Combinational logic and sequential logic are the building blocks of digital system design. Introduce several structural and behavioral models for synchronous sequential circuits. A tracebased method for delay fault diagnosis in synchronous.
Later, we will study circuits having a stored internal state, i. The sequential control circuit can be instructed to test any of a number of circuits by executing one of several fixed sequences. Testing of vlsi circuits me vlsi design materials,books. Introduction digital systems produced today are extremely complex in nature. Benchmarking diagnosis algorithms with a diverse set of ic. On the other side, diagnosis of delay faults has received attention for the. Fault diagnosis in sequential circuits 19 which distinguishes the most faults which have not yet been distinguished, should be selected first.
Electronic testing and fault diagnosis 3rd edition loveday, g. This paper presents a novel fault diagnosis method for analog circuits using ensemble empirical mode decomposition eemd, relative entropy, and extreme learning machine elm. Pdf on redundancy and fault detection in sequential circuits. In previous works of these authors, a technique for doing single fault diagnosis in linear analog circuits was developed. In this work, the multiple observation times approach is applied to fault location.
The model takes locality aspect of errors and is based on a 3value, nonenumerative analysis technique. We also show that some faults in sequential circuits, which are undetectable by. Diagnostic fault simulation of sequential circuits citeseerx. Jan 12, 2019 in this tutorial, we will learn about sequential circuits, what is sequential logic, how are sequential circuits different from combinational circuits, different types of sequential circuits, a few important sequential circuits basics and many more. This method is an outgrowth of our previous work on delay fault diagnosis in combinational circuits, and is therefore based on a path tracing algorithm appropriate for sequential circuits. Sinclair electronics fault diagnosis fountain press argus books ltd. In this paper we present a new approach to fault diagnosis in sequential circuits based on an effectcause analysis. Clearly, the number of fault pairs is much larger than the number of faults thus making this problem very difficult and challenging. Studies show the effectiveness of the region based model for single and multiple stuck faults and gate connection errors.
1367 639 957 1545 41 96 733 931 165 54 489 697 1542 147 665 1098 1389 1074 200 648 237 1326 629 521 443 900 393 1479 1355 108 1440