D. Arumí;S. Manich;A. Gómez-Pau;R. Rodríguez-Montañés;M. B. González;F. Campabadal
{"title":"True Random Number Generator Based on RRAM-Bias Current Starved Ring Oscillator","authors":"D. Arumí;S. Manich;A. Gómez-Pau;R. Rodríguez-Montañés;M. B. González;F. Campabadal","doi":"10.1109/JXCDC.2023.3320056","DOIUrl":"https://doi.org/10.1109/JXCDC.2023.3320056","url":null,"abstract":"This work presents a resistive random access memory (RRAM)-bias current-starved ring oscillator (CSRO) as true random number generator (TRNG), where the cycle-to-cycle variability of an RRAM device is exploited as source of randomness. A simple voltage divider composed of this RRAM and a resistor is considered to bias the gate terminal of the extra transistor of every current starved (CS) inverter of the ring oscillator (RO). In this way, the delay of the inverters is modified, deriving an unpredictable oscillation frequency every time the RRAM switches to the high resistance state (HRS). The oscillation frequency is finally leveraged to extract the sequence of random bits. The design is simple and adds low area overhead. Experimental measurements are performed to analyze the cycle-to-cycle variability in the HRS. The very same measurements are subsequently used to validate the TRNG by means of electrical simulations. The obtained results passed all the National Institute of Standards and Technology randomness tests (NIST) tests without the need for postprocessing.","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 2","pages":"92-98"},"PeriodicalIF":2.4,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10268070","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"109229885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"XNOR-VSH: A Valley-Spin Hall Effect-Based Compact and Energy-Efficient Synaptic Crossbar Array for Binary Neural Networks","authors":"Karam Cho;Akul Malhotra;Sumeet Kumar Gupta","doi":"10.1109/JXCDC.2023.3320677","DOIUrl":"10.1109/JXCDC.2023.3320677","url":null,"abstract":"Binary neural networks (BNNs) have shown an immense promise for resource-constrained edge artificial intelligence (AI) platforms. However, prior designs typically either require two bit-cells to encode signed weights leading to an area overhead, or require complex peripheral circuitry. In this article, we address this issue by proposing a compact and low power in-memory computing (IMC) of XNOR-based dot products featuring signed weight encoding in a single bit-cell. Our approach utilizes valley-spin Hall (VSH) effect in monolayer tungsten di-selenide to design an XNOR bit-cell (named “XNOR-VSH”) with differential storage and access-transistor-less topology. We co-optimize the proposed VSH device and a memory array to enable robust in-memory dot product computations between signed binary inputs and signed binary weights with sense margin (SM)\u0000<inline-formula> <tex-math>$1 ~mu text{A}$ </tex-math></inline-formula>\u0000. Our results show that the proposed XNOR-VSH array achieves 4.8%–9.0% and 37%–63% lower IMC latency and energy, respectively, with 49%–64% smaller area compared to spin-transfer-torque (STT)-magnetic random access memory (MRAM) and spin-orbit-torque (SOT)-MRAM based XNOR-arrays. We also present the impact of hardware non-idealities and process variations in XNOR-VSH on system-level accuracy for the trained ResNet-18 BNNs using the CIFAR-10 dataset.","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 2","pages":"99-107"},"PeriodicalIF":2.4,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10268108","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135845097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Many-Body Effects-Based Invertible Logic With a Simple Energy Landscape and High Accuracy","authors":"Yihan He;Chao Fang;Sheng Luo;Gengchiau Liang","doi":"10.1109/JXCDC.2023.3320230","DOIUrl":"https://doi.org/10.1109/JXCDC.2023.3320230","url":null,"abstract":"Inspired by many-body effects, we propose a novel design for Boltzmann machine (BM)-based invertible logic (IL) using probabilistic bits (p-bits). A CMOS-based XNOR gate is derived to serve as the hardware implementation of many-body interactions, and an IL family is built based on this design. Compared to the conventional two-body-based design framework, the many-body-based design enables compact configuration and provides the simplest binarized energy landscape for fundamental IL gates; furthermore, we demonstrate the composability of the many-body-based IL circuit by merging modular building blocks into large-scale integer factorizers (IFs). To optimize the energy landscape of large-scale combinatorial IL circuits, we introduce degeneracy in energy levels, which enlarges the probabilities for the lowest states. Circuit simulations of our IFs reveal a significant boost in factorization accuracy. An example of a 2- \u0000<inline-formula> <tex-math>$times2$ </tex-math></inline-formula>\u0000-bit IF demonstrated an increment of factorization accuracy from 64.99% to 91.44% with a reduction in the number of energy levels from 32 to 9. Similarly, our 6- \u0000<inline-formula> <tex-math>$times6$ </tex-math></inline-formula>\u0000-bit IF increases the accuracy from 4.430% to 83.65% with the many-body design. Overall, the many-body-based design scheme provides promising results for future IL circuit designs.","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 2","pages":"83-91"},"PeriodicalIF":2.4,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/6570653/10288180/10266315.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49964659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Modeling and Evaluation of Echo-State Networks Using Spin Torque Nano-Oscillators","authors":"Siyuan Qian;Shaloo Rakheja","doi":"10.1109/JXCDC.2023.3317240","DOIUrl":"10.1109/JXCDC.2023.3317240","url":null,"abstract":"An echo state network (ESN), capable of processing time-series data with high accuracy, is designed and benchmarked using spin torque nano-oscillators (STNOs) with easy-plane anisotropy. An ESN belongs to the category of reservoir computers, where the reservoir comprises a randomly initialized, recurrently connected, and untrained pool of neurons and acts as a high-dimensional expansion of the input signal. The readout function is used to glean a meaningful output representation. Here, we use STNOs as the basic building block of the ESN and apply the ESN to predict the Mackey–Glass (MG) time-series data. The design parameters of the STNO and the input data representation are selected to yield prediction errors as low as \u0000<inline-formula> <tex-math>$4times 10^{-3}$ </tex-math></inline-formula>\u0000. We also quantify the short-term memory (STM) and the parity-check (PC) capacity of the ESN and obtain metrics that are comparable to or better than existing spintronics-based ESNs, as well as ESNs employing “tanh” neurons. The peak STM is found to be approximately 8.8, while the peak PC capacity is found to be approximately 3.9. The impacts of thermal fluctuations and process variability on ESN performance are systematically quantified. Although the ESN’s prediction and memory capability remain robust with temperature variations, a 10% variation in the dimensions of the STNO free layer can lead to around 40% increase in its prediction error for the MG time-series data.","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 2","pages":"134-142"},"PeriodicalIF":2.4,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10255553","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135551560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Matthew Spear;Joshua E. Kim;Christopher H. Bennett;Sapan Agarwal;Matthew J. Marinella;T. Patrick Xiao
{"title":"The Impact of Analog-to-Digital Converter Architecture and Variability on Analog Neural Network Accuracy","authors":"Matthew Spear;Joshua E. Kim;Christopher H. Bennett;Sapan Agarwal;Matthew J. Marinella;T. Patrick Xiao","doi":"10.1109/JXCDC.2023.3315134","DOIUrl":"10.1109/JXCDC.2023.3315134","url":null,"abstract":"The analog-to-digital converter (ADC) is not only a key component in analog in-memory computing (IMC) accelerators but also a bottleneck for the efficiency and accuracy of these systems. While the tradeoffs between power consumption, latency, and area in ADC design are well studied, it is relatively unknown which ADC implementations are optimal for algorithmic accuracy, particularly for neural network inference. We explore the design space of the ADC with a focus on accuracy, investigating the sensitivity of neural network outputs to component variability inside the ADC and how this sensitivity depends on the ADC architecture. The compact models of the pipeline, cyclic, successive-approximation-register (SAR) and ramp ADCs are developed, and these models are used in a system-level accuracy simulation of analog neural network inference. Our results show how the accuracy on a complex image recognition benchmark (ResNet50 on ImageNet) depends on the capacitance mismatch, comparator offset, and effective number of bits (ENOB) for each of the four ADC architectures. We find that robustness to component variations depends strongly on the ADC design and that inference accuracy is particularly sensitive to the value-dependent error characteristics of the ADC, which cannot be captured by the conventional ENOB precision metric.","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 2","pages":"176-184"},"PeriodicalIF":2.4,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10250846","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135402296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An Qi Zhang;Amr M. S. Tosson;Dylan Ma;Ryan Fang;Lan Wei
{"title":"Stuck-at Faults Tolerance and Recovery in MLP Neural Networks Using Imperfect Emerging CNFET Technology","authors":"An Qi Zhang;Amr M. S. Tosson;Dylan Ma;Ryan Fang;Lan Wei","doi":"10.1109/JXCDC.2023.3313127","DOIUrl":"10.1109/JXCDC.2023.3313127","url":null,"abstract":"Devices using emerging technologies and materials with the potential to outperform their silicon counterpart are actively explored in search of ways to extend Moore’s law. Among these technologies, low dimensional channel materials (LDMs) devices, such as carbon nanotube field-effect transistors (CNFETs), are promising to eventually outperform silicon CMOS. As these technologies are in their early development stages, their devices still suffer from high levels of defects and variations, thus unsuitable for nowadays general-purpose applications. On the other hand, applications with inherent error resilience and high-performance demands would suppress the impact of process imperfection and benefit from the performance boost. These applications, including image processing and machine learning through neural networks, would be the ideal targets for adopting these new emerging technologies even in their early stage of technology and process development. In this article, the effects of stuck-at faults in CNFET static random access memory (SRAM)-based multilayer perceptron (MLP) neural network are investigated. The impacts of various fault patterns are analyzed. Several fault recovery techniques are introduced, and their effectiveness is analyzed under different scenarios. With the proposed recovery techniques, the system can recover and tolerate a high level of stuck-at faults up to 40%, paving the path to adopt the early-stage and faulty emerging devices technologies in such high-demand applications.","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 2","pages":"168-175"},"PeriodicalIF":2.4,"publicationDate":"2023-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10246789","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135361608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Modeling of Bilayer Modulated RRAM and Its Array Performance for Compute-in-Memory Applications","authors":"Jia-Wei Lee;Tzu-Chin Chou;Po-An Chen;Meng-Hsueh Chiang","doi":"10.1109/JXCDC.2023.3311899","DOIUrl":"10.1109/JXCDC.2023.3311899","url":null,"abstract":"This article presents a modified compact model of resistive random access memory (RRAM) with a tunneling barrier. The bilayer modulated RRAM can be integrated into a higher density array, reducing leakage current in standby mode. The model demonstrates current transition behavior from low- to high-bias regions by considering both bulk-limited and electrode-limited transport mechanisms. This model can evaluate RRAM array performance under various pulsing conditions and device parameter variations with calibrated model cards. The compute-in-memory application requires precise current sum results hindered by the wire resistance loading effect. This study also evaluates various sizes of arrays suitable for performance improvement.","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 2","pages":"151-158"},"PeriodicalIF":2.4,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10239165","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"62236596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrea Boni;Francesco Malena;Francesco Saccani;Michele Amoretti;Michele Caselli
{"title":"Boosting RRAM-Based Mixed-Signal Accelerators in FD-SOI Technology for ML Applications","authors":"Andrea Boni;Francesco Malena;Francesco Saccani;Michele Amoretti;Michele Caselli","doi":"10.1109/JXCDC.2023.3309713","DOIUrl":"10.1109/JXCDC.2023.3309713","url":null,"abstract":"This article presents the flipped (F)-2T2R resistive random access memory (RRAM) compute cell enhancing the performance of RRAM-based mixed-signal accelerators for deep neural networks (DNNs) in machine-learning (ML) applications. The F-2T2R cell is designed to exploit the features of the FD-SOI technology and it achieves a large increase in cell output impedance, compared to the standard 1-transistor 1-resistor (1T1R) cell. The article also describes the modeling of an F-2T2R-based accelerator and its transistor-level implementation in a 22-nm FD-SOI technology. The modeling results and the accelerator performance are validated by simulation. The proposed design can achieve an energy efficiency of up to 1260 1 bit-TOPS/W, with a memory array of 256 rows and columns. From the results of our analytical framework, a ResNet18, mapped on the accelerator, can obtain an accuracy reduction below 2%, with respect to the floating-point baseline, on the CIFAR-10 dataset.","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 2","pages":"159-167"},"PeriodicalIF":2.4,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10233848","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"62236587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"3-D Logic Circuit Design-Oriented Electrothermal Modeling of Vertical Junctionless Nanowire FETs","authors":"Sara Mannaa;Arnaud Poittevin;Cédric Marchand;Damien Deleruyelle;Bastien Deveautour;Alberto Bosio;Ian O’Connor;Chhandak Mukherjee;Yifan Wang;Houssem Rezgui;Marina Deng;Cristell Maneux;Jonas Müller;Sylvain Pelloquin;Konstantinos Moustakas;Guilhem Larrieu","doi":"10.1109/JXCDC.2023.3309502","DOIUrl":"10.1109/JXCDC.2023.3309502","url":null,"abstract":"This work presents new insights into 3-D logic circuit design with vertical junctionless nanowire FETs (VNWFET) accounting for underlying electrothermal phenomena. Aided by the understanding of the nanoscale heat transport in VNWFETs through multiphysics simulations, the SPICE-compatible compact model captures temperature and trapping effects principally through a shift of the device threshold voltage. Circuit-level simulations indicate a strong impact of temperature variation on functionality and figures of merits, such as energy-delay products. Subsequent guidelines for design considerations are discussed that are intended to provide feedback for technology improvements.","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 2","pages":"116-123"},"PeriodicalIF":2.4,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10232986","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"62236510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"INFORMATION FOR AUTHORS","authors":"","doi":"10.1109/JXCDC.2023.3277781","DOIUrl":"https://doi.org/10.1109/JXCDC.2023.3277781","url":null,"abstract":"","PeriodicalId":54149,"journal":{"name":"IEEE Journal on Exploratory Solid-State Computational Devices and Circuits","volume":"9 1","pages":"C3-C3"},"PeriodicalIF":2.4,"publicationDate":"2023-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/6570653/10138050/10168535.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49946610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}