Pub Date : 2025-02-26DOI: 10.1109/OJCAS.2025.3545904
Konstantinos Metaxas;Vassilis Alimisis;Costas Oustoglou;Yannis Kominis;Paul P. Sotiriadis
A comprehensive nonlinear analysis of autonomous and periodically forced fully-differential, negative-resistor LC oscillators is presented. Through nonlinear transformations in the state space, it is shown that oscillators within this class exhibit qualitatively similar dynamical behavior in terms of their limit cycles and bifurcation curves, at least within an open region containing the origin. The case of autonomous, complementary BJT oscillators is used to validate the qualitative analysis and demonstrate a general approach of how to numerically extend the bifurcation curves away from the equilibrium point and determine the oscillatory conditions. When external periodic force is present, we focus on the special case of periodically multiplicatively-forced fully-differential, negative-resistor, LC oscillators and use Harmonic Balance techniques to derive analytical expressions estimating the locking range in the weak injection regime. The results are used to calculate the locking range of a harmonically forced complementary BJT oscillator yielding explicit expressions closely aligned with experimental measurements, thus verifying the validity of the analysis.
{"title":"Nonlinear Analysis of Differential LC Oscillators and Injection Locked Frequency Dividers","authors":"Konstantinos Metaxas;Vassilis Alimisis;Costas Oustoglou;Yannis Kominis;Paul P. Sotiriadis","doi":"10.1109/OJCAS.2025.3545904","DOIUrl":"https://doi.org/10.1109/OJCAS.2025.3545904","url":null,"abstract":"A comprehensive nonlinear analysis of autonomous and periodically forced fully-differential, negative-resistor LC oscillators is presented. Through nonlinear transformations in the state space, it is shown that oscillators within this class exhibit qualitatively similar dynamical behavior in terms of their limit cycles and bifurcation curves, at least within an open region containing the origin. The case of autonomous, complementary BJT oscillators is used to validate the qualitative analysis and demonstrate a general approach of how to numerically extend the bifurcation curves away from the equilibrium point and determine the oscillatory conditions. When external periodic force is present, we focus on the special case of periodically multiplicatively-forced fully-differential, negative-resistor, LC oscillators and use Harmonic Balance techniques to derive analytical expressions estimating the locking range in the weak injection regime. The results are used to calculate the locking range of a harmonically forced complementary BJT oscillator yielding explicit expressions closely aligned with experimental measurements, thus verifying the validity of the analysis.","PeriodicalId":93442,"journal":{"name":"IEEE open journal of circuits and systems","volume":"6 ","pages":"100-109"},"PeriodicalIF":2.4,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10904493","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637833","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}
Pub Date : 2025-02-04DOI: 10.1109/OJCAS.2025.3538707
Yufei Xiao;Kai Cai;Xiaohu Ge;Yong Xiao
Energy consumption evaluation for data processing tasks, such as encoding and decoding, is a critical consideration in designing very large scale integration (VLSI) circuits. Incorporating both information theory and circuit perspectives, a new general energy consumption model is proposed to capture the energy consumption of channel decoder circuits. For the binary erasure channel, lower bounds of energy consumption are derived for two-dimensional (2D) and three-dimensional (3D) decoder circuits under specified error probabilities, along with scaling rules for energy consumption in each case. Based on the proposed model, the lower bounds of energy consumption for staged serial and parallel implementations are derived, and a specific threshold value is identified to determine the parallel or serial decoding in decoder circuits. Staged serial implementations in 3D decoder circuits achieve a higher energy efficiency than fully parallel implementations when the processed data exceed 48 bits. Simulation results further demonstrate that the energy efficiency of 3D decoders improves with increasing data volume. When the number of input bits is 648, 1296 and 1944, the energy consumption of 3D decoders is reduced by 11.58%, 13.07%, and 13.86% compared to 2D decoders, respectively. The energy consumption of 3D decoders surpasses that of 2D decoders when the decoding error probability falls below a specific threshold of 0.035492. These results provide a foundational framework and benchmarks for analyzing and optimizing the energy consumption of 2D and 3D channel decoder circuits, enabling more efficient VLSI circuit designs.
{"title":"Energy Consumption Modeling of 2-D and 3-D Decoder Circuits","authors":"Yufei Xiao;Kai Cai;Xiaohu Ge;Yong Xiao","doi":"10.1109/OJCAS.2025.3538707","DOIUrl":"https://doi.org/10.1109/OJCAS.2025.3538707","url":null,"abstract":"Energy consumption evaluation for data processing tasks, such as encoding and decoding, is a critical consideration in designing very large scale integration (VLSI) circuits. Incorporating both information theory and circuit perspectives, a new general energy consumption model is proposed to capture the energy consumption of channel decoder circuits. For the binary erasure channel, lower bounds of energy consumption are derived for two-dimensional (2D) and three-dimensional (3D) decoder circuits under specified error probabilities, along with scaling rules for energy consumption in each case. Based on the proposed model, the lower bounds of energy consumption for staged serial and parallel implementations are derived, and a specific threshold value is identified to determine the parallel or serial decoding in decoder circuits. Staged serial implementations in 3D decoder circuits achieve a higher energy efficiency than fully parallel implementations when the processed data exceed 48 bits. Simulation results further demonstrate that the energy efficiency of 3D decoders improves with increasing data volume. When the number of input bits is 648, 1296 and 1944, the energy consumption of 3D decoders is reduced by 11.58%, 13.07%, and 13.86% compared to 2D decoders, respectively. The energy consumption of 3D decoders surpasses that of 2D decoders when the decoding error probability falls below a specific threshold of 0.035492. These results provide a foundational framework and benchmarks for analyzing and optimizing the energy consumption of 2D and 3D channel decoder circuits, enabling more efficient VLSI circuit designs.","PeriodicalId":93442,"journal":{"name":"IEEE open journal of circuits and systems","volume":"6 ","pages":"74-84"},"PeriodicalIF":2.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10870295","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553307","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}
Pub Date : 2025-01-27DOI: 10.1109/OJCAS.2025.3533978
{"title":"2024 Index IEEE Open Journal of Circuits and Systems Vol. 5","authors":"","doi":"10.1109/OJCAS.2025.3533978","DOIUrl":"https://doi.org/10.1109/OJCAS.2025.3533978","url":null,"abstract":"","PeriodicalId":93442,"journal":{"name":"IEEE open journal of circuits and systems","volume":"5 ","pages":"408-417"},"PeriodicalIF":2.4,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10854515","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143106066","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}
Pub Date : 2025-01-09DOI: 10.1109/OJCAS.2025.3525785
{"title":"IEEE Circuits and Systems Society","authors":"","doi":"10.1109/OJCAS.2025.3525785","DOIUrl":"https://doi.org/10.1109/OJCAS.2025.3525785","url":null,"abstract":"","PeriodicalId":93442,"journal":{"name":"IEEE open journal of circuits and systems","volume":"6 ","pages":"C2-C2"},"PeriodicalIF":2.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10834607","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142938460","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}
Pub Date : 2024-12-31DOI: 10.1109/OJCAS.2024.3524363
Sayma Nowshin Chowdhury;Matthew Chen;Sahil Shah
Floating-gate transistors provide non-volatile analog storage in standard CMOS processes and are crucial in the development of reconfigurable Systems on Chips (SoCs), programmable analog structures, analog neural networks, and mixed-signal neuromorphic circuits. Designing and fabricating these circuits typically involves extensive SPICE-based simulations, yet integrating and calibrating floating-gate transistors post-fabrication is a common practice. To bridge this gap, we present a Verilog-A model based on empirical measurements for a floating-gate transistor fabricated using a 65 nm CMOS process. This model incorporates mechanisms for hot-electron injection and Fowler-Nordheim tunneling, and accurately predicts retention time, thus facilitating the design of adaptive peripheral circuits. Our findings offer insights into optimizing floating-gate transistors for enhanced programming efficiency and reduced area consumption.
{"title":"Analysis and Verilog-A Modeling of Floating-Gate Transistors","authors":"Sayma Nowshin Chowdhury;Matthew Chen;Sahil Shah","doi":"10.1109/OJCAS.2024.3524363","DOIUrl":"https://doi.org/10.1109/OJCAS.2024.3524363","url":null,"abstract":"Floating-gate transistors provide non-volatile analog storage in standard CMOS processes and are crucial in the development of reconfigurable Systems on Chips (SoCs), programmable analog structures, analog neural networks, and mixed-signal neuromorphic circuits. Designing and fabricating these circuits typically involves extensive SPICE-based simulations, yet integrating and calibrating floating-gate transistors post-fabrication is a common practice. To bridge this gap, we present a Verilog-A model based on empirical measurements for a floating-gate transistor fabricated using a 65 nm CMOS process. This model incorporates mechanisms for hot-electron injection and Fowler-Nordheim tunneling, and accurately predicts retention time, thus facilitating the design of adaptive peripheral circuits. Our findings offer insights into optimizing floating-gate transistors for enhanced programming efficiency and reduced area consumption.","PeriodicalId":93442,"journal":{"name":"IEEE open journal of circuits and systems","volume":"6 ","pages":"63-73"},"PeriodicalIF":2.4,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10818976","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143107177","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}
Pub Date : 2024-12-17DOI: 10.1109/OJCAS.2024.3517215
{"title":"IEEE Circuits and Systems Society","authors":"","doi":"10.1109/OJCAS.2024.3517215","DOIUrl":"https://doi.org/10.1109/OJCAS.2024.3517215","url":null,"abstract":"","PeriodicalId":93442,"journal":{"name":"IEEE open journal of circuits and systems","volume":"5 ","pages":"C2-C2"},"PeriodicalIF":2.4,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10805493","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142858870","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}
Pub Date : 2024-12-17DOI: 10.1109/OJCAS.2024.3517219
{"title":"Instruction for Authors","authors":"","doi":"10.1109/OJCAS.2024.3517219","DOIUrl":"https://doi.org/10.1109/OJCAS.2024.3517219","url":null,"abstract":"","PeriodicalId":93442,"journal":{"name":"IEEE open journal of circuits and systems","volume":"5 ","pages":"408-408"},"PeriodicalIF":2.4,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10805492","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142843066","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}
Pub Date : 2024-12-16DOI: 10.1109/OJCAS.2024.3472124
Patrick Wiegand;Sebastian Simmich;Fatih Ilgaz;Franz Faupel;Benjamin Spetzler;Robert Rieger
An application specific integrated circuit (ASIC) and a custom-made microelectromechanical system (MEMS) sensor are presented, designed to function together as a sensor system for measuring low amplitude low frequency magnetic fields. The MEMS system comprises several free-standing double-wing magnetoelectric resonators with a size of $900~mu $