Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4484042
Byunghyun Lee, Taewhan Kim
A dynamic monitoring of thermal behavior of hardware resources using thermal sensors is very important to maintain the operation of systems safe and reliable. This work proposes an effective solution to the problem of thermal sensor allocation and placement for reconfigurable systems at the post-manufacturing stage. Specifically, we define the sensor allocation and placement problem (SAPP), and propose a solution which formulates SAPP into the unate-covering problem (UCP) and solves it optimally. We then provide an extended solution to handle a practical design issue where the hardware resources for the sensor implementation on specific array locations have already been used up by the application logic. Experimental results using MCNC benchmarks show that our proposed technique uses 19.7% less number of sensors to monitor hotspots on the average than that used by the bisection based (Mukherjee et al., 2006) approaches.
利用热传感器对硬件资源的热行为进行动态监测，对维护系统的安全可靠运行具有重要意义。这项工作提出了一个有效的解决方案，热传感器的分配和安置在可重构系统的后制造阶段的问题。具体来说，我们定义了传感器的分配与放置问题(SAPP)，并提出了一种将SAPP转化为覆盖问题(UCP)的解决方案。然后，我们提供了一个扩展的解决方案来处理一个实际的设计问题，其中用于在特定阵列位置上实现传感器的硬件资源已经被应用程序逻辑用完。使用MCNC基准的实验结果表明，我们提出的技术使用的传感器数量平均比基于对分法(Mukherjee et al.， 2006)的方法少19.7%。
{"title":"Optimal allocation and placement of thermal sensors for reconfigurable systems and its practical extension","authors":"Byunghyun Lee, Taewhan Kim","doi":"10.1109/ASPDAC.2008.4484042","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4484042","url":null,"abstract":"A dynamic monitoring of thermal behavior of hardware resources using thermal sensors is very important to maintain the operation of systems safe and reliable. This work proposes an effective solution to the problem of thermal sensor allocation and placement for reconfigurable systems at the post-manufacturing stage. Specifically, we define the sensor allocation and placement problem (SAPP), and propose a solution which formulates SAPP into the unate-covering problem (UCP) and solves it optimally. We then provide an extended solution to handle a practical design issue where the hardware resources for the sensor implementation on specific array locations have already been used up by the application logic. Experimental results using MCNC benchmarks show that our proposed technique uses 19.7% less number of sensors to monitor hotspots on the average than that used by the bisection based (Mukherjee et al., 2006) approaches.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"443 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125763856","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}
Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4483984
Alexander Jesser, L. Hedrich
In this paper we firstly introduce a novel symbolic model checker (MScheck) for mixed-signal circuits. MScheck is capable to conflate the continuous behavior, typical for analog designs, and the discrete behavior in the digital domain for formal verification. Timing information of both systems will be symbolically stored within multi terminal binary decision diagrams (MTBDDs) for the entire verification procedure. The effectiveness of our approach is demonstrated on a phase locked loop (PLL) by formal verification of the locking property.
{"title":"A symbolic approach for mixed-signal model checking","authors":"Alexander Jesser, L. Hedrich","doi":"10.1109/ASPDAC.2008.4483984","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4483984","url":null,"abstract":"In this paper we firstly introduce a novel symbolic model checker (MScheck) for mixed-signal circuits. MScheck is capable to conflate the continuous behavior, typical for analog designs, and the discrete behavior in the digital domain for formal verification. Timing information of both systems will be symbolically stored within multi terminal binary decision diagrams (MTBDDs) for the entire verification procedure. The effectiveness of our approach is demonstrated on a phase locked loop (PLL) by formal verification of the locking property.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"31 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131453968","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}
Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4484039
Farhad Mehdipour, Hamid Noori, M. S. Zamani, Koji Inoue, K. Murakami
In the design process of a reconfigurable accelerator employing in an embedded system, multitude parameters may result in remarkable complexity and a large design space. Design space exploration as an alternative to the quantitative approach can be employed to find a right balance between the different design parameters. In this paper, a hybrid approach is introduced to analytically explore the design space for a coarse grain accelerator and determine a wise design point exploiting data extracted from applications, quantitatively. It also provides flexibility for taking into account new design constraints as well as new characteristics of applications. Furthermore, this approach is a methodological approach which reduces the design time and results in a point which satisfies the design goals.
{"title":"Design space exploration for a coarse grain accelerator","authors":"Farhad Mehdipour, Hamid Noori, M. S. Zamani, Koji Inoue, K. Murakami","doi":"10.1109/ASPDAC.2008.4484039","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4484039","url":null,"abstract":"In the design process of a reconfigurable accelerator employing in an embedded system, multitude parameters may result in remarkable complexity and a large design space. Design space exploration as an alternative to the quantitative approach can be employed to find a right balance between the different design parameters. In this paper, a hybrid approach is introduced to analytically explore the design space for a coarse grain accelerator and determine a wise design point exploiting data extracted from applications, quantitatively. It also provides flexibility for taking into account new design constraints as well as new characteristics of applications. Furthermore, this approach is a methodological approach which reduces the design time and results in a point which satisfies the design goals.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"424 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122959354","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}
Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4483963
Feng Wang, Xiaoxia Wu, Yuan Xie
Increasing delay and power variation are significant challenges to the designers as technology scales to the deep sub-micron (DSM) regime. Traditional module selection techniques in high level synthesis use worst case delay/power information to perform the optimization, and therefore may be too pessimistic such that extra resources are used to guarantee design requirements. Parametric yield, which is defined as the probability of the synthesized hardware meeting the performance/power constraints, can be used to guide design space exploration. The parametric yield can be effectively improved by combining both design-time variation-aware optimization and post silicon tuning techniques (such as adaptive body biasing (ABB)). In this paper, we propose a module selection algorithm that combines design-time optimization with post- silicon tuning (using ABB) to maximize design yield. A variation-aware module selection algorithm based on efficient performance and power yield gradient computation is developed. The post silicon optimization is formulated as an efficient sequential conic program to determine the optimal body bias distribution, which in turn affects design-time module selection. The experiment results show that significant yield can be achieved compared to traditional worst-case driven module selection technique. To the best of our knowledge, this is the first variability-driven high level synthesis technique that considers post-silicon tuning during design time optimization.
{"title":"Variability-driven module selection with joint design time optimization and post-silicon tuning","authors":"Feng Wang, Xiaoxia Wu, Yuan Xie","doi":"10.1109/ASPDAC.2008.4483963","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4483963","url":null,"abstract":"Increasing delay and power variation are significant challenges to the designers as technology scales to the deep sub-micron (DSM) regime. Traditional module selection techniques in high level synthesis use worst case delay/power information to perform the optimization, and therefore may be too pessimistic such that extra resources are used to guarantee design requirements. Parametric yield, which is defined as the probability of the synthesized hardware meeting the performance/power constraints, can be used to guide design space exploration. The parametric yield can be effectively improved by combining both design-time variation-aware optimization and post silicon tuning techniques (such as adaptive body biasing (ABB)). In this paper, we propose a module selection algorithm that combines design-time optimization with post- silicon tuning (using ABB) to maximize design yield. A variation-aware module selection algorithm based on efficient performance and power yield gradient computation is developed. The post silicon optimization is formulated as an efficient sequential conic program to determine the optimal body bias distribution, which in turn affects design-time module selection. The experiment results show that significant yield can be achieved compared to traditional worst-case driven module selection technique. To the best of our knowledge, this is the first variability-driven high level synthesis technique that considers post-silicon tuning during design time optimization.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124464869","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}
Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4484000
Kui Wang, Hao Fang, Hu Xu, Xu Cheng
We propose a fast clock skew scheduling algorithm which minimizes clock period and enlarges the slacks of timing critical paths. To reduce the runtime of the timing analysis engine, our algorithm allows the sequential graph to be partly extracted. And the runtime of itself is almost linear to the size of the extracted sequential graph. Experimental results show its runtime is less than a minute for a design with more than ten thousands of flip-flops.
{"title":"A fast incremental clock skew scheduling algorithm for slack optimization","authors":"Kui Wang, Hao Fang, Hu Xu, Xu Cheng","doi":"10.1109/ASPDAC.2008.4484000","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4484000","url":null,"abstract":"We propose a fast clock skew scheduling algorithm which minimizes clock period and enlarges the slacks of timing critical paths. To reduce the runtime of the timing analysis engine, our algorithm allows the sequential graph to be partly extracted. And the runtime of itself is almost linear to the size of the extracted sequential graph. Experimental results show its runtime is less than a minute for a design with more than ten thousands of flip-flops.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121050060","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}
Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4483974
Yongqiang Lyu, Qing Su, J. Kawa
As device technology continues to scale past 65 nm, the heavy application of resolution enhancement techniques (RET) makes the complexity, run time and quality issues in mask data preparation (MDP) grow severely. As one major and core step in MDP, polygon partitioning converts the complex layout shapes into trapezoids suitable for mask writing. The partitioning run time and quality of the resulting polygon partitions directly impacts the cost, integrity, and quality of the written mask. In this work, we introduce an innovative approach to solve the polygon partition problem by constructing a variant Steiner minimal tree: minimal partition tree (MPT). We prove the equivalence between MPT and the optimal polygon partition. Also, the solution search space for MPT is further reduced for the efficiency of the MPT algorithms. Finally, a generic MPT algorithm flow and a linear-time heuristic algorithm based on it are proposed. Experiments show that MPT solves the polygon partitioning with very promising and high quality results.
{"title":"An innovative Steiner tree based approach for polygon partitioning","authors":"Yongqiang Lyu, Qing Su, J. Kawa","doi":"10.1109/ASPDAC.2008.4483974","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4483974","url":null,"abstract":"As device technology continues to scale past 65 nm, the heavy application of resolution enhancement techniques (RET) makes the complexity, run time and quality issues in mask data preparation (MDP) grow severely. As one major and core step in MDP, polygon partitioning converts the complex layout shapes into trapezoids suitable for mask writing. The partitioning run time and quality of the resulting polygon partitions directly impacts the cost, integrity, and quality of the written mask. In this work, we introduce an innovative approach to solve the polygon partition problem by constructing a variant Steiner minimal tree: minimal partition tree (MPT). We prove the equivalence between MPT and the optimal polygon partition. Also, the solution search space for MPT is further reduced for the efficiency of the MPT algorithms. Finally, a generic MPT algorithm flow and a linear-time heuristic algorithm based on it are proposed. Experiments show that MPT solves the polygon partitioning with very promising and high quality results.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116258103","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}
Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4483961
Katsumi Homma, Izumi Nitta, Toshiyuki Shibuya
Statistical timing analysis (SSTA) is a method that calculates circuit delay statistically with process parameter variations, die-to-die (D2D) and within-die (WID) variations. In this paper, we model that WID parameter variations are independent for each cell and line in a chip and D2D variations are governed by one variation on a chip. We propose a new method of computing a full chip delay distribution considering both D2D and WID parameter variations. Experimental results show that the proposed method is more accurate than previous methods on actual chip designs.
{"title":"Non-Gaussian Statistical Timing models of die-to-die and within-die parameter variations for full chip analysis","authors":"Katsumi Homma, Izumi Nitta, Toshiyuki Shibuya","doi":"10.1109/ASPDAC.2008.4483961","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4483961","url":null,"abstract":"Statistical timing analysis (SSTA) is a method that calculates circuit delay statistically with process parameter variations, die-to-die (D2D) and within-die (WID) variations. In this paper, we model that WID parameter variations are independent for each cell and line in a chip and D2D variations are governed by one variation on a chip. We propose a new method of computing a full chip delay distribution considering both D2D and WID parameter variations. Experimental results show that the proposed method is more accurate than previous methods on actual chip designs.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126884654","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}
Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4484006
Takashi Sato, Hiroyuki Ueyama, N. Nakayama, K. Masu
A procedure that decomposes measured parametric device variation into systematic and random components is studied by considering the decomposition process as selecting the most suitable model for describing on-die spatial variation trend. In order to maximize model predictability, the log-likelihood estimate called corrected Akaike information criterion is adopted. Depending on on-die contours of underlying systematic variation, necessary and sufficient complexity of the systematic regression model is objectively and adaptively determined. The proposed procedure is applied to 90-nm threshold voltage data and found the low order polynomials describe systematic variation very well. Designing cost-effective variation monitoring circuits as well as appropriate model determination of on-die variation are hence facilitated.
{"title":"Determination of optimal polynomial regression function to decompose on-die systematic and random variations","authors":"Takashi Sato, Hiroyuki Ueyama, N. Nakayama, K. Masu","doi":"10.1109/ASPDAC.2008.4484006","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4484006","url":null,"abstract":"A procedure that decomposes measured parametric device variation into systematic and random components is studied by considering the decomposition process as selecting the most suitable model for describing on-die spatial variation trend. In order to maximize model predictability, the log-likelihood estimate called corrected Akaike information criterion is adopted. Depending on on-die contours of underlying systematic variation, necessary and sufficient complexity of the systematic regression model is objectively and adaptively determined. The proposed procedure is applied to 90-nm threshold voltage data and found the low order polynomials describe systematic variation very well. Designing cost-effective variation monitoring circuits as well as appropriate model determination of on-die variation are hence facilitated.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124904598","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}
Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4484053
D. Grabowski, M. Olbrich, E. Barke
The impact of parameter variations in integrated analog circuits is usually analyzed by Monte Carlo methods with a high number of simulation runs. Few approaches based on interval arithmetic were not successful due to tremendous overapproximations. In this paper, we describe an innovative approach computing transient and DC simulations of nonlinear analog circuits with symbolic range representations that keeps correlation information, and hence has a very limited overapproximation. The methods are based on affine and quadratic arithmetic. Ranges are represented by unique symbols so that linear correlation information is preserved. We demonstrate feasibility of the methods by simulation results using complex analog circuits.
{"title":"Analog circuit simulation using range arithmetics","authors":"D. Grabowski, M. Olbrich, E. Barke","doi":"10.1109/ASPDAC.2008.4484053","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4484053","url":null,"abstract":"The impact of parameter variations in integrated analog circuits is usually analyzed by Monte Carlo methods with a high number of simulation runs. Few approaches based on interval arithmetic were not successful due to tremendous overapproximations. In this paper, we describe an innovative approach computing transient and DC simulations of nonlinear analog circuits with symbolic range representations that keeps correlation information, and hence has a very limited overapproximation. The methods are based on affine and quadratic arithmetic. Ranges are represented by unique symbols so that linear correlation information is preserved. We demonstrate feasibility of the methods by simulation results using complex analog circuits.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125235582","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}
Pub Date : 2008-01-21DOI: 10.1109/ASPDAC.2008.4483975
Ming-Chao Tsai, Yung-Chia Lin, Ting-Chi Wang
Phase shifting mask (PSM) is a promising resolution enhancement technique, which is used in the deep sub-wavelength lithography of the VLSI fabrication process. However, applying the PSM technique requires the layout to be free of phase conflicts. In this paper, we present a mixed integer linear programming (MILP) based layout modification algorithm which solves the phase conflict problem by wire spreading. Unlike existing layout modification methods which first solve the phase conflict problem by removing edges from the layout-associated conflict graphs and then try to revise the layout to match the resultant conflict graphs, our algorithm simultaneously considers the phase conflict problem and the feasibility of modifying the layout. The experimental results indicate that without increasing the chip size, the phase conflict problem can be well tackled with minimal perturbation to the layout.
{"title":"An MILP-based wire spreading algorithm for PSM-aware layout modification","authors":"Ming-Chao Tsai, Yung-Chia Lin, Ting-Chi Wang","doi":"10.1109/ASPDAC.2008.4483975","DOIUrl":"https://doi.org/10.1109/ASPDAC.2008.4483975","url":null,"abstract":"Phase shifting mask (PSM) is a promising resolution enhancement technique, which is used in the deep sub-wavelength lithography of the VLSI fabrication process. However, applying the PSM technique requires the layout to be free of phase conflicts. In this paper, we present a mixed integer linear programming (MILP) based layout modification algorithm which solves the phase conflict problem by wire spreading. Unlike existing layout modification methods which first solve the phase conflict problem by removing edges from the layout-associated conflict graphs and then try to revise the layout to match the resultant conflict graphs, our algorithm simultaneously considers the phase conflict problem and the feasibility of modifying the layout. The experimental results indicate that without increasing the chip size, the phase conflict problem can be well tackled with minimal perturbation to the layout.","PeriodicalId":277556,"journal":{"name":"2008 Asia and South Pacific Design Automation Conference","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123501858","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}
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