IEEE/CAM Information Theory Workshop at Cornell最新文献_第4页

Error Control to Increase the Yield of Semiconductor RAM's 提高半导体RAM成品率的误差控制

IEEE/CAM Information Theory Workshop at Cornell Pub Date : 1989-06-25 DOI: 10.1109/ITW.1989.761432

R. Krishnamoorthy, C. Heegard

{"title":"Error Control to Increase the Yield of Semiconductor RAM's","authors":"R. Krishnamoorthy, C. Heegard","doi":"10.1109/ITW.1989.761432","DOIUrl":"https://doi.org/10.1109/ITW.1989.761432","url":null,"abstract":"A hard defect in a semiconductor random access memory (RAM) is a cell which is \"stuck-at\" a certain value or is otherwise consistently unreliable. The most commonly used technique to correct hard defects during manufacturing is row/column replacement, wherein redundant rows and columns are added on to each memory array and are used to replace rows and columns which contain defective cells. This method has been applied to memory chips of modest sizes (in the 64 K - 4 M bit range). However, the strategy of replacing an entire row or column because of a single defective cell seems likely to be inefficient as the size of the memory array grows. Our research effort was motivated by a recent paper [l] in which this technique is shown to be asymptotically ineffective: as the size of the memory array grows, regardless of the rate (the amount of redundancy) the probability of obtaining an error-free array approaches zero. We consider implementing an error correcting code (ECC) on the memory array in order to control hard defects. A simple single-errorcorrecting code is used over the rows, each row containing an integral number of codewords. Since each codeword can tolerate up to one defect, this technique allows the array to suffer some defective cells and still exhibit no loss of fidelity. We analyze the yield (the probability that a chip is defect-free) due to this method, using a shortenend Hamming code to illustrate our results. The presence of multiple defective cells in some codewords would cause these codewords to become undecodable, causing the chip to be rejected. In order to further improve the yield, we also consider using redundant rows and columns in conjunction with an ECC to correct undecodable codewords in the memory array. It is to be noted that we are interested in improving the yield of memory chips which suffer from single cell defects. In the case of an entire row or column failing (due to the failure of a row driver or a column decoder) we cannot, of course, do any better than to replace the entire row or column. Algorithms to switch rows and columns are examined, and three separate cases are considered: (1) redundant rows, (2) redundant columns, and (3) redundant rows and columns. Case (1) is easily analyzed. Cases (2) and (3) are much more difficult: it is shown that the problem of finding an optimal algorithm to switch columns (case (2)) is inherently intractable, and we prove that this problem is NP - complete. As a corollary, the problem of simultaneously switching rows and columns is also shown to be NP - complete. Heuristics for cases (2) and (3) are presented, and bounds on the yield due to these techniques are derived. References","PeriodicalId":413028,"journal":{"name":"IEEE/CAM Information Theory Workshop at Cornell","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128527234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Code Construction Methods for Error Discriminating and Unidirectional Error Control Codes 错误识别和单向错误控制码的编码构造方法

IEEE/CAM Information Theory Workshop at Cornell Pub Date : 1989-06-25 DOI: 10.1109/ITW.1989.761434

Tae Nam Ahn, T. Rao, K. Sakaniwa

引用次数: 1

On the Successive Refinement of Information 论信息的逐次细化

IEEE/CAM Information Theory Workshop at Cornell Pub Date : 1989-06-25 DOI: 10.1109/ITW.1989.761420

T. Cover, W. Equitz

引用次数: 1

Bayesian Estimation: Information-Theoretic Analysis and Applications 贝叶斯估计:信息论分析与应用

IEEE/CAM Information Theory Workshop at Cornell Pub Date : 1989-06-25 DOI: 10.1109/ITW.1989.761422

B. Clarke

{"title":"Bayesian Estimation: Information-Theoretic Analysis and Applications","authors":"B. Clarke","doi":"10.1109/ITW.1989.761422","DOIUrl":"https://doi.org/10.1109/ITW.1989.761422","url":null,"abstract":"It is known that the optimal redundancy of a source code behaves like one half the dimension of the parameter times the log of the sample size. We give an asymptotic expression for the redundancy which is valid for smooth parametric families of distributions equipped with a prior. Important terms include one half the logarithm of the determinant of the Fisher information matrix, minus the logarithm of the prior density and a constant arising from the mean of a Chi-square distribution. The dominant terms arise from an integration by Laplace's method. Our formula can be integrated with respect to the prior distribution on the parameter, under some conditions, so as to give the average redundancy and the minimax redundancy. The minimax code uses Jeff reys' prior. The same expansion has implications for channel coding: Consider channels which have a continuous d-dimensional input alphabet and a k-dimensional output alphabet (where the coordinates of the output are conditionally independent of the input). A message for this channel is Cooperatively encoded by d transmitters and cooperatively decoded by n receivers. For a large number of receivers the mutual information behaves like (d/ 2) logk , that is, one half the number of transmitters times the log of the number of receivers. From the estimation standpoint we have approximated three forms of the cumulative risk under relative entropy loss. Our asymptotic expansions give the risk, the Bayes risk, and the minimax risk. The cumulative risk of the Bayes estimator occurs naturally as the error exponent in a hypothesis test. It also occurs naturally in proving that the standardized posterior converges to a normal.","PeriodicalId":413028,"journal":{"name":"IEEE/CAM Information Theory Workshop at Cornell","volume":"151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121185854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Distance Preserving Run-length Limited Codes 距离保持行长有限码

IEEE/CAM Information Theory Workshop at Cornell Pub Date : 1989-03-28 DOI: 10.1109/ITW.1989.761428

C. A. French

引用次数: 16

Exponential Sums and Goppa Codes 指数和与Goppa码

IEEE/CAM Information Theory Workshop at Cornell Pub Date : 1900-01-01 DOI: 10.1109/ITW.1989.761396

C. Moreno, O. Moreno

引用次数: 3

Matched Spectral Null Codes for Partial Response Channels 部分响应信道的匹配频谱空码

IEEE/CAM Information Theory Workshop at Cornell Pub Date : 1900-01-01 DOI: 10.1109/ITW.1989.761405

R. Karabed, P. Siegel

引用次数: 4

Statistical Neurodynamics 统计神经动力学

IEEE/CAM Information Theory Workshop at Cornell Pub Date : 1900-01-01 DOI: 10.1109/itw.1989.761435

S. Amari

引用次数: 4