In  the statistical timing analysis is performed to calculate the circuit timing behavior by considering spatial correlations into account. Finding the delay distribution of one critical path at a time is not enough. So, spatial correlation between the paths are taken into account to find the maximum if path delay faults and so as to compute the probability of delay failures. In  the propagation time of each delay path is computed and the clock period is set to 110% of the longest delay path in the circuit. In  the lower bound on number of tests is performed in order to locate delay faults in combinational circuits. Two pattern tests are applied and the number of rising and falling transitions is computed based on the type of gates. In  and  the BISTimplementation for the delay fault testing is done to ensure the correct working of circuit in functional mode. In  the longest path is selected based upon the maximum delay among all the paths. In this paper the modes in the circuit are controlled by separate pin and the implementation is done successfully.
This paper introduces the function of test cases with minimal power for Built-In-Self-Test (BIST) implementation. This method intends Test-Per-Scan (TPS) based test cases using Multiple Single Input Change (MSIC) architecture. Multiple SIC patterns are developed by using EX-OR operation of twisted ring counter and test design algorithms like Linear Feedback Shift Register (LFSR),Bit-Swapping LFSR (BSLFSR), and Cellular Automata (CA). These patterns are used to a diminish number of transitions in the test patterns that are generated. The preferred method uses Test-Per-Scan technique for generating Multiple SIC test patterns. TPS diminished the power consumption during test mode. The seed generator used in TPS is modified LFSR ’ s i.e., BS-LFSR, Cellular Automata (CA). BS-LFSR is composed of with an LFSR with a multiplexer. In CA, it also presents a variation on a BIST technique, which is from a one-dimensional cellular automaton; the pseudo random bit generator is generated. The proposed Hybrid Cellular Automata (HCA) using the rules 90 and 150 to generate the pseudo random designs. Moreover, the CA implementations illustrates properties of data compression like LFSRs and that they exhibit locally and with topological consistency significant attributes for a VLSI design. In this proposed method, LFSR is replaced with BS-LFSR, and HCA. Simulation and synthesis outcome with ISCAS c432 benchmark determine that Multiple SIC can reduce the power consumption.
We use the same LFSR for both pseudorandom pattern generation and deterministic phases. First, we propose a new algorithm to select a proper primitive polynomial; after that the LP deterministic BIST and LP reseeding schemes are presented. Some extra variables are injected just like EDT .We propose a new scheme to select the size of the LFSR and the number of extra variables simultaneously in order to minimize the amount of deterministic test data. Usually, a small LFSR constructed by a primitive polynomial is sufficient when a well-designed PS is adopted in the pseudorandom testing phase. In our method, a combination of a small LFSR and the PS is used to generate test patterns in the pseudorandom testing phase. The weighted test-enable signal-based pseudorandom test generator generates weighted pseudorandom test patterns. The size of the LFSR is not determined by the maximum number of care bits for any deterministic test vector. That is, the same LFSR is used for both phases.
The requirement of the today’s hardware designs is low power circuit implementation of BIST based logic circuits on FPGA to achieve high speed operational circuits. Reference  shows an advanced BIST architecture with Low Power LBIST and BDS oriented March Algorithm for Intra Word Coupling Faults. This paper addresses read faults with classic faults with an improvement in the efficiency of the architecture and test time in detecting the faults. In the present paper a critical consideration is given to low power BISTimplementation. A multiplier with two 4-bit inputs is taken as a test design for low power implementation on FPGA with self-test capability. The self-test feature is provided using a low-power test pattern generator design. The test pattern is designed using a modified architecture by reducing the number of sequential component as compared to the conventional design components. The present paper is organized as follows: Section-II describes the design of Test Pattern Generator and Multiplier that are implemented in this work. Section-III presents simulation and synthesis results. Section-IV presents the conclusion drawn on the basis of the performed design. Finally the references are mentioned.
Test cost becomes a significant contributor to the production cost. Efforts to reduce the manufacturing cost require the need of BISTimplementation in contrast to Automatic Test Equipment (ATE) which results in higher capital and operational cost. It helps reduction of test time as it reduces the switching time of ATE instruments and measurement of complex circuitry using low cost testing solutions. In most Built-in-Self-Test (BIST) techniques, a small piece of circuit is added to the design in order to convert the system response to a simpler form with lower frequency that makes on-chip analysis feasible. The Radio Frequency (RF) to low frequency conversion in BIST can be enabled using peak, power, or envelope detectors.
It is observed that the total power consumed in low transition LFSR and the power consumed in conventional LFSR is 54% less than the power consumption by conventional LFSR. It is concluded that low power LFSR is very useful for BISTimplementation in which the CUT may be Combinational, sequential and memory circuits. Using low power LFSR technique we can further decrease the power in BISTimplementation.
Abstract— The main objective of this research is to design a Built-in self-test (BIST) technique based on pseudo-exhaustive testing. Two pattern test generator is used to provide high fault coverage. To provides fault coverage of detectable combinational faults with minimum number of test patterns than the conventional exhaustive test pattern generation, increases the speed of BIST and may posses minimum Hardware Utilization. A Built-in self-test (BIST) is a commonly used design technique that allows a circuit to test itself.Built-in self-test (BIST) technique based on pseudo-exhaustive testing, two pattern test generator is used to provide high fault coverage. It is widely known that a large class of physical defects cannot be modelled as stuck-at faults. For example, a transistor stuck- open fault in a CMOS circuit can convert a combinational circuit under test (CUT) into a sequential one, while a delay fault may cause circuit malfunction at clock speed, although it does not affect the steady-state operation. Detection of such faults requires two-pattern tests. It is proposed to design a BIST circuit for fault detection using pseudo exhaustive two pattern generator using minimum hardware utilization and increasing the speed of BIST.
In this brief, a novel input vector monitoring concurrent BIST scheme is proposed, which compares favorably to previously proposed schemes with respect to the hard- ware overhead/CTL tradeoff. BIST schemes constitute an attractive solution to the problemof testing VLSI de- vices. Input vector monitoring concurrent BISTschemes perform testing during the circuit normal operation with- outimposing a need to set the circuit offline to perform the test, thereforethey can circumvent problems appear- ing in offline BIST techniques. The evaluation criteria for this class of schemes are the hardware overhead and the CTL, i.e., the time required for the test to complete,while the circuit operates normally. In this brief, a novel input vectormonitoring concurrent BIST architecture has been presented, basedon the use of a SRAM-cell
VLSI testing problems like Test generation problems, input combinatorial problems, gate to I/O pin ratio problems are discussed  and this motivated designers to identify reliable test methods in solving these difficulties. An insertion of special test circuitry on the VLSI circuit that allows efficient test coverage is the answer to the problem. It is addressed by the need of design for testability (DFT) using BIST circuit. BIST is an on-chip test logic that is utilized to test the functional logic of a chip, by itself. With the rapid increase in the design complexity, BIST has become a major design consideration in DFT methods and is becoming increasingly important in today’s state of the art SoCs. A properly designed BIST is able to offset the cost of added test hardware while at the same time ensuring the reliability, testability and reduces maintenance cost. BIST solution consists of an Automatic Test Pattern Generator (ATPG), the circuit to be tested, a way to analyze the results, and a way to compress those results for simplicity and handling. Fig. 1 shows a BIST module composition. Generic BIST architecture components  are;
Öz: 24 Kasım 2015 tarihinde Suriye sınırında, sınır ihlali yapan Rus savaş uçağının Türk savaş uçakları tarafından düşürülmesi iki ülke ilişkileri açısından ciddi sorunlara neden olmuştur. Olay sonrasında Rusya, Türkiye ile olan tüm askeri ve ekonomik ilişkilerini tek taraflı olarak dondurmuş ve Türkiye’ye ekonomik yaptırımlar uygulama kararı almıştır. Söz konusu yaptırım kararlarından, başta turizm ve gıda sektörü olmak üzere birçok sektör doğrudan etkilenmiştir. Bu kapsamda, çalışmanın amacı BIST Gıda, İçecek ve BIST Turizm Endeksleri’nde yer alan şirketlerin hisse senetlerinin bu olaya nasıl tepki verdikleri Olay Çalışması (Event Study) yöntemi kullanılarak ortaya çıkarmaktır. Elde edilen bulgulara göre, BIST Gıda, İçecek Endeksi’ne kote olan şirketlerin olaya genel olarak negatif tepki verdikleri gözlemlenirken, BIST Turizm Endeksi’nde yer alan şirketlerin olay sonrası dönemde pozitif AR değerleri sergiledikleri tespit edilmiştir. Diğer taraftan, Kümülatif Ortalama Anormal Getiri (CAAR) değerlerinin çoğunluğunun negatif oluşu dikkat çekmiştir. Ayrıca, tahmin edilebilir belirgin bir trend olmasa da olay penceresinde bazı günlerde istatistiksel olarak anlamlı sonuçların bulunması piyasanın yarı güçlü formda etkin olmadığını göstermiştir.
technology library of 0.35 micron. All the area ﬁgures are in terms of equivalent gates and the delay in nano-seconds. Table 1 compiles the results for the optimised designs for a given set of user priorities. In the Table 1 columns 2-4 shows the frozen design ﬁgures as per the left-bottom of the design space as described in Figure 4, whereas columns 5- 7 contains the results when the BIST cost estimations are used as per our estimation criteria. The last column shows the percentage BIST cost improvement. Table 2 shows the synthesis statistics for the designs. Columns 2-3 represents the initially maximally serial implementation statistics of FUs and registers and illustrate the size of the design space. As can be observed that the the active trade off of the testability by the proposed heuristic produce better self- testable sets of designs. The important aspect of the com- parison is that the final self-testable designs are not neces- sarily have the same structure which are designed otherwise without embedded BIST resource cost. The extensive search can result in better optimisation and generation of different self-testable designs for the same behaviour. In FFT, the accumulated design area for the self-testable design is re- duced by 1.68%, the penalty paid is in terms of increased delay of the design. Similarly, for QRS the cumulative area improvement is 3.4%. The design DHRC could not achieve the gain from this heuristic for the given optimisation sched- ule by degrading the design area by almost 1%, but resulted in a faster implementation for the given behaviour.
In this paper, we assume that the Combinational CUT has primary and state inputs, and employs full- scan. Even though the proposed BIST TPG is applicable to scan designs with multiple scan chains, we assume that all primary and state inputs are driven by a single scan chain unless stated otherwise (application to multiple scan chains is discussed separately) only for clarity and convenience of illustration. A test cube is a test pattern that has unspecified inputs. The detection probability of a fault is defined as the probability that a randomly generated test pattern detects the fault. In the 3-weight WRBIST scheme, fault coverage for a random pattern resistant circuit is enhanced by improving detection probabilities of RPRFs; the detection probability of an RPRF is improved by fixing some inputs of the CUT to the values specified in a deterministic test cube for the RPRF.
Feedback Shift Register capable of generating a given finite sequence. On the BIST design stage and considering the fault-free test response sequence, the BMA is used to synthesize an LFSR capable of generating this sequence in an economical way. A testing for the interesting Built- in Self-Test technique  for the minimal number of test patterns .It requires predefined fault coverage. The technique is not applicable for the existing deterministic test pattern generators. It has enormous consumers of overhead silicon area. A new low power BIST test pattern generator that provides test vectors which can reduce the switching activity during test operation . It has been implemented based on an LFSR-based TPG, but can also be designed using a cellular automata. A new BIST TPG design that is comprised of an Adjacency-based TPG plus a conventional pseudo-random TPG  (i.e. a LFSR).When used to generate test patterns for test-per-clock BIST, it reduced the number of transitions that occur in the CUT and hence decreases the average and peak power consumption during testing. Low ower consumption during scan-based testing . The testing process has two modes they are shift and capture modes. The circuit reliability is high during manufacturing test. The work proposed a novel X- filling technique, namely “infill”, to address the above issue, by analyzing the impact of X-bits on switching activities of the circuit nodes in the two different phases. In addition, different from prior X-filling methods for shift-power reduction that can only reduce shift-in power. The BIST techniques based on reseeding of multiple- polynomial linear feedback shift registers . This scheme encodes deterministic test sets at distinctly lower costs than previously known approaches. In this work it is shown how this scheme can be supported during test pattern generation. The
Günümüzde yatırım kararlarında rasyonel hareket eden yatırımcılar için finansal performans göstergeleri tek başına yeterli olmamaktadır. Özellikle 1990’lı yılların sonunda ve 2000’li yılların başında yaşanan muhasebe tabanlı şirket skandalları, yatırımcıları kar elde etme kadar yatırımlarını geri alma motivasyonuyla da hareket etmeye zorlamıştır. Yatırım araçlarının volatiliteleri ise yatırımın riskliliğine ilişkin gösterge olmasından dolayı son yıllarda yatırımcılar tarafından yaygınca kullanılmaya başlamıştır. Bu çalışmanın amacı, BİST-50 endeksinin 2007- 2016 dönemi için günlük kapanış değerleri üzerinden volatilite yapısını tespit etmektir. BİST-50 endeksinin asimetrik durumunun da ortaya çıkarılması amacıyla iki doğrusal (ARCH ve GARCH) modelin yanında üç asimetrik (PARCH, EGARCH ve TGARCH) model de analiz kapsamında test edilmiştir. Analiz bulgularına göre endeksin volatilite yapısını GARCH(2,1) modeli açıklamaktadır. BİST-50 endeksinin volatilite ısrarcılığı 16.14 gün, günlük volatilitesi ise %1.76 olarak hesaplanmıştır.
Built-in Self-Test (BIST) techniques constitute an attractive and practical solution to the problem of testing VLSI circuits. BIST eliminates the necessity of high-bandwidth test interactions and allows at speed testing (time difference between launch and capture event). Other advantages of BIST include reduced product development cycle and cost effective system maintenance. BIST techniques are typically classified into two types: offline and online.
The ever increasing demand for portable computing devices and wireless communication sys- tems requires low power very large scale integration (VLSI) circuits. Minimizing power dis- sipation during the VLSI design flow clearly increases lifetime and reliability of the circuit. Numerous techniques for low power VLSI circuit design have been reported  for comple- mentary metal-oxide semiconductor (CMOS) technology, where the dominant factor of power dissipation is dynamic power dissipation caused by switching activity . While these tech- niques have successfully reduced the circuit power dissipation during functional operation, test- ing of such low power circuits has recently become an area of concern mainly because of the following two reasons. Firstly, it was reported in  that there is significantly higher switch- ing activity during testing than during functional operation and hence higher power dissipation. This can decrease the reliability of the circuit under test (CUT) due to excessive temperature and current density which cannot be tolerated by circuits designed using power minimization tech- niques. Secondly, high switching activity during test application leads to manufacturing yield loss which can be explained as follows . High switching activity during test application causes high rate of current flowing in power and ground lines leading to excessive power/ground noise and large resistive voltage drop. Resistive voltage drop caused by large maximum instan- taneous current flowing in the power lines is underestimated by state of the art approaches  since they assume signal correlations that are destroyed when employing design for test (DFT) methodologies, such as scan or built-in self-test (BIST). Therefore, high power/ground noise combined with large resistive voltage drop can erroneously change the logic state of circuit lines causing some good circuits to fail the test, leading to unnecessary loss of manufacturing yield. Consequently, addressing the problems associated with testing low power VLSI circuits has become an important issue. It is shown in this paper how power dissipation is related to different BIST parameters. Prior to explaining the motivational experimental results presented in this paper, the sources of higher power dissipation during test application are discussed and shortcomings of the previous approaches are outlined.
information/yield apparatus for a considerable length of time is still generally utilized. The extra BIST circuit that expands the equipment overhead builds configuration time and size of the chip, which may debase the execution. This paper concentrates on the outline of a UART chip with inserted BIST engineering utilizing straightforward LFSR with the assistance of VHDL dialect. The paper depicts the issues of (VLSI) testing took after by the conduct of UART that incorporates both transmitter and collector area utilizing VHISC Hardware Description Language (VHDL) .
Assessing credit risk allows financial institutions to plan future loans freely, to achieve targeted risk management and gain maximum profitability. In this study, the constructed risk assessment models are on a sample data which consists of financial ratios of enterprises listed in the Bourse Istanbul (BIST). 356 enterprises are classified into three levels as the investment, speculative and below investment groups by ten parameters. The applied methods are discriminant analysis, k nearest neighbor (k-NN), support vector machines (SVM), decision trees (DT) and a new hybrid model, namely Artificial Neural Networks with Adaptive Neuro-Fuzzy Inference Systems (ANFIS). This study will provide a comparison of models to build better mechanisms for preventing risk to minimize the loss arising from defaults. The results indicated that the decision tree models achieve a superior accuracy for the prediction of failure. The model we proposed as an innovation has an adequate performance among the applied models
returns of stocks before the companies were included in the BIST Participation 30 Index, and the decline continued on the date of the event and following days. The table values shows that a statistically significant but negative results were obtained at 1% 5% and 10% significance levels, on the date of the event and following days. Accordingly, it can be said that the inclusion of companies in the participation index has a negative effect on the price of the stocks. This result suggests that the investors, who benefits mainly from the fundamental analysis methods in their investment decisions, might show adverse reaction by considering that the financial leverage effect and accordingly profits would decrease in the companies included in the participation index. As it is known, financial leverage is a criterion that shows the effect of any change in operating profit (interest and profit before tax) on earnings per share and this effect is measured by the degree of financial leverage (DFL). Borrowing of interest against loans, interest income (financing expenses) of the operating profit with the reduction of net profit and profit per share, the increase in the operating profit brings a greater increase than the increase of operation profit. Therefore, the financial leverage effect will be at a very low level or not at all in companies with little or no debt (DFL = 1). It is considered that the interest rate loans received in the companies that are included in the participation index cannot exceed a certain rate due to the financial criteria and that the investors explain why they may have such a reaction. In addition, the finding of study that the inclusion of the companies in the BIST Participation 30 Index has a statistically significant but negative impact on the stock prices, assuming that securities prices in an advanced capital market reflect all kinds of securities information and hence the invalidity of the Effective Markets Hypothesis that no investor has a chance to beat the market.