{"title":"Hardware Efficiency Stochastic Computing based on Hybrid Spatial Coding","authors":"Yakun Zhou, Yizhuo Zhou, Jiajun Yan, Jienan Chen","doi":"10.1145/3565478.3572535","DOIUrl":"https://doi.org/10.1145/3565478.3572535","url":null,"abstract":"As the era of silicon-based microchips advances by Moores Law approach to physical limits, new computational paradigms are proposed for future systems, i.e., stochastic computation. However, the current stochastic computing faces the challenge of high latency and low accuracy. In this work, we propose spatial coding based on the hybrid stochastic computation (SHSC) method, which is a stochastic-binary hybrid domain computation. Instead of sequential bits computing, the proposed SHSC expands stochastic bits in the spatial dimension. To balance the accuracy and complexity, the multiplication is divided into high and low precision parts, where the high precision parts are performed in the binary domain, and low precision parts are performed in the stochastic domain. A low-cost error compensation circuit is proposed to further improve the computation accuracy. According to the implementation outcomes, the proposed method exhibits a 28% hardware efficiency improvement with the same inference accuracy as traditional neural network applications.","PeriodicalId":125590,"journal":{"name":"Proceedings of the 17th ACM International Symposium on Nanoscale Architectures","volume":"339 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122755112","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}
Soyed Tuhin Ahmed, Kamal Danouchi, Christopher Münch, G. Prenat, Anghel Lorena, Mehdi B. Tahoori
{"title":"Binary Bayesian Neural Networks for Efficient Uncertainty Estimation Leveraging Inherent Stochasticity of Spintronic Devices","authors":"Soyed Tuhin Ahmed, Kamal Danouchi, Christopher Münch, G. Prenat, Anghel Lorena, Mehdi B. Tahoori","doi":"10.1145/3565478.3572536","DOIUrl":"https://doi.org/10.1145/3565478.3572536","url":null,"abstract":"In the age of automation, machine learning systems for real-time critical decisions in various domains such as autonomous driving are at an all-time high. Predictive uncertainty allows a machine learning system to make more insightful decisions by avoiding blind predictions. Algorithmically, Bayesian neural networks (BayNNs) based on dropout are principled methods for estimating predictive uncertainty in a machine learning application. However, the computational cost and power consumption make the use of BayNNs on embedded hardware unattractive. Hardware accelerators with emerging non-volatile resistive memories (NVMs) such as Magnetic Tunnel Junction (MTJ) in conjunction with quantized models are an interesting option for efficient implementations of such a system. Binary BayNNs are a desirable alternative that can provide predictive uncertainty efficiently by combining the benefits of quantization and hardware acceleration. In this paper, propose for the first time the binary bayesian neural network (BayBNN) using dropout-based approximation, and we leverage the inherent randomness of spin-tronic devices for in-memory Bayesian inference. Our proposed method can detect up-to 100% of the out-of-distribution data, improve inference accuracy by 15% for corrupted data, and ~ 2% for in-distribution data.","PeriodicalId":125590,"journal":{"name":"Proceedings of the 17th ACM International Symposium on Nanoscale Architectures","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125987844","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}
{"title":"A Multi-Level Simulation of GeH FETs: From Nanomaterial and Device Characteristics to Circuit Performance Optimization","authors":"Yiju Zhao, Y. Yoon, Lan Wei","doi":"10.1145/3565478.3572533","DOIUrl":"https://doi.org/10.1145/3565478.3572533","url":null,"abstract":"Here, we demonstrate a multi-level simulation for 2D material-based nanoelectronics, including material parameterization, device simulation, physics-based compact modeling, and circuit benchmark. We perform quantum transport simulations based on the Non-equilibrium Green's Function (NEGF) method to calculate the characteristics of two-dimensional (2D) GeH field-effect transistors (FETs). We have developed a compact model by modifying the original virtual source (VS) model to capture the unique behaviors of 2D-material FETs such as voltage-dependent VS velocity and quantum capacitance. HSPICE circuit simulation is then conducted for circuit analyses and optimization of CMOS digital benchmark circuits. Our simulation results show that energy-delay product can be lowered by 50 times if power supply and threshold voltages are properly engineered. This study not only provides a seamless multi-level simulation process to fill a gap between the properties of nanomaterials and the behavior of circuits based on novel FETs, but also advances in-depth understanding of material, device and circuit in a comprehensive manner. It is expected that the suggested approach could be further extended to a framework for 2D material-device-circuit co-optimization processes.","PeriodicalId":125590,"journal":{"name":"Proceedings of the 17th ACM International Symposium on Nanoscale Architectures","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128826321","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}
{"title":"Capacity-oriented High-performance NV-TCAM Leveraging Hybrid MRAM Scheme","authors":"Didi Zhang, Bi Wu, Haonan Zhu, Weiqiang Liu","doi":"10.1145/3565478.3572315","DOIUrl":"https://doi.org/10.1145/3565478.3572315","url":null,"abstract":"As a special type of memory, Ternary Content Addressable Memory (TCAM) has been widely employed in network routers and various applications that require high speed table lookup. However, the large cell area and high static power consumption of traditional CMOS-based TCAMs have always constrained its advance toward higher capacity. Therefore, many non-volatile memory devices, such as ReRAM, FeFET, and MRAM, are emerging in TCAM designs to address these issues. However, SOT-MRAM devices with ultra-high write speed, low power consumption and small cell area are not effectively utilized in TCAM designs due to their low tunnel magnetoresistance (TMR) ratio, etc. In this work, first, combining the ultra-high performance of SOT-MRAM and the reliability of STT-MRAM, a 4T-3MTJ SOT/STT hybrid NV-TCAM structure with ultra-high integration density is proposed. However, to eliminate the lower match line utilization caused by the low TMR of SOT-MRAM, another highly reliable 7T-3MTJ NV-TCAM structure is proposed. Simulation results show that the proposed two TCAM structures can achieve search speed of 0.4ns and 0.15ns with only 4 and 7 transistors, respectively. While maintaining high performance, their write energy is only 0.133pJ/bit, a maximum reduction of 91.6% over existing TCAM designs. Meanwhile, the array-level simulations prove the great potential of the proposed design in terms of integration density and performance.","PeriodicalId":125590,"journal":{"name":"Proceedings of the 17th ACM International Symposium on Nanoscale Architectures","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133127457","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}
Mengxin Zheng, Qian Lou, Fan Chen, Lei Jiang, Yongxin Zhu
{"title":"CryptoLight: An Electro-Optical Accelerator for Fully Homomorphic Encryption","authors":"Mengxin Zheng, Qian Lou, Fan Chen, Lei Jiang, Yongxin Zhu","doi":"10.1145/3565478.3572544","DOIUrl":"https://doi.org/10.1145/3565478.3572544","url":null,"abstract":"Fully homomorphic encryption (FHE) protects data privacy in cloud computing by enabling computations to directly occur on cipher-texts. To improve the time-consuming FHE operations, we present an electro-optical (EO) FHE accelerator, CryptoLight. Compared to prior FHE accelerators, on average, CryptoLight reduces the latency of various FHE applications by >94.4% and the energy by >95%.","PeriodicalId":125590,"journal":{"name":"Proceedings of the 17th ACM International Symposium on Nanoscale Architectures","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115867086","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}
{"title":"Proceedings of the 17th ACM International Symposium on Nanoscale Architectures","authors":"","doi":"10.1145/3565478","DOIUrl":"https://doi.org/10.1145/3565478","url":null,"abstract":"","PeriodicalId":125590,"journal":{"name":"Proceedings of the 17th ACM International Symposium on Nanoscale Architectures","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131641399","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}