Circuit Performance Research Articles

A novel nanosheet reconfigurable field effect transistor with dual-doped source/drain

—In this paper, a reconfigurable field-effect transistor (RFET) with dual-doped nanosheet architecture and triple independent gates is proposed and studied with the numerical simulations. The proposed RFET can behave as either an n/p-type MOSFET or an n/p-type tunneling-FET (TFET) according to different program biases. A comprehensive study is carried out on the device mechanism and the influence of key device parameters. Various metrics, such as the on-state current (ION), off-state current (IOFF), ION/IOFF, threshold voltage (VT) and sub-threshold swing (SS), are used to evaluate the proposed RFET. This RFET combining the advantages of the conventional MOSFETs (High ION and operation speed) and the new emerging TFETs (Low IOFF, sub-threshold swing and power dissipation) could make the circuit design more flexible and high efficiency, and improve the circuit performance.

Small-Scale Power Plants Based on Organic Rankine cycle (ORC) using Low-Boiling Fluorocarbon Working Fluids when Operating at High Initial Cycle Conditions

The purpose of the work is to develop and analyze the operation of a thermal circuit based on the organic Rankine cycle (ORC) using low-boiling working substances of the fluorocarbon class when operating at high initial cycle parameters. This goal is achieved by energy analysis of single- and multi-stage thermal circuits of power plants with a turbine circuit operating on low-boiling fluorocarbon work-ing substances, such as octafluoropropane C3F8 and decafluorobutane C4F10. It is proposed to integrate the ORC thermal circuit as an extension to a small-capacity gas turbine power plant (GTU), operating on synthesis gas after a biomass gasifier. The most important results of the work are the possibility of implementing a cycle with a low condensation temperature of the medium, which allows, when using low-boiling working fluids, to significantly reduce the temperature of the heat removal process and, consequently, increase the efficiency of the cycle. The possibility of using the listed working substances in power plants with a turbine circuit, which until now have been used mainly as refrigerants for refrig-eration and heat pump systems, has been shown. The significance of the results of the work lies in the fact that, based on the analysis of the energy complex, a circuit solution has been proposed and justified that can increase the energy efficiency of the power supply complex, increasing the volume of generated electrical power and providing a number of technological and environmental advantages.

Real time performance assessment of utility grid interfaced solar photovoltaic plant

Continuous monitoring of large-scale solar photovoltaic (PV) installations is necessary to check the deterioration and monitor the performance of the PV plant. Fault diagnosis is crucial to ensure the PV plant operates safely and reliably. This paper presents a diagnosis methodology based on current-voltage (I-V) and PV characteristics to monitor and assess the behavior of solar PV. In this paper, I-V curve characterization using an I-V curve tracer is used to check the deterioration and diagnosis of the PV panels. The real-time performance of the 50.4 kWp rooftop solar grid interfaced PV plant is investigated and analyzed using I-V and PV curve tracers in real-time conditions. The overall performance of solar PV is assessed on a real-time test system in different scenarios such as variable climatic conditions, partial shading conditions, aging of solar panels, short circuit conditions, and dust decomposition. Furthermore, the performance assessment of solar PV is evaluated using performance indicators such as open circuit voltage index, short circuit current index, fill factor, and performance ratio.

Control of Carbon Dioxide Bivalent Heat Pump on Heating of Buildings

The scheme of a bivalent heat pump (BHP) is considered, using both the heat of the water from the return network and the heat of the outside air as low-potential heat sources (LPH). The aim of the work is to create a BHP circuit that provides functioning at the variable heat load temperature. The goal was achieved by solving the following problems: analysis of methods of synthesis of BHP circuits, analysis of circuit operation under random disturbances and development of the automatic control systems for BHP. The most significant result of the work is: a heat pump circuit that can operate at variable pressures of the evaporator and the gas cooler. The next significant result is, for bivalent heat pumps intended for operation in heat supply systems with qualitative and qualitative-quantitative laws of thermal control, the introduction into the heat pump circuit of a heat exchanger installed in the return water circuit of the secondary building and cooled by outside air, as well as two control valves installed in series between the gas cooler and the evaporator, the first valve installed along the refrigerant flow being controlled by a signal based on the pressure difference between the outlet of the gas cooler and the separation vessel between the evaporator and the gas cooler, and the second by pressure in front of the evaporator. The significance of the obtained results lies in the increase of the COP of the heat pump, due to the increase of heat transfer in the gas cooler circuit. The HHP circuit differs from the known ones in that it uses two control valves and the heat exchanger for additional cooling of the return water of the BHP heated building.

Controllable and reusable seesaw circuit based on nicking endonucleases

Seesaw circuits are essential for molecular computing and biosensing. However, a notable limitation of seesaw circuits lies in the irreversible depletion of components, precluding the attainment of system recovery and rendering nucleic acid circuits non-reusable. We developed a brand-new method for creating controllable and reusable seesaw circuits. By using the nicking endonucleases Nt.BbvCI and Nt.Alwi, we removed “functional components” while keeping the “skeletal components” for recurrent usage. T-inputs were introduced, increasing the signal-to-noise ratio of AND logic from 2.68 to 11.33 and demonstrating compatibility. We identified the logic switching feature and verified that it does not impair circuit performance. We also built intricate logic circuits, such as OR-AND gate, to demonstrate the versatility of our methodology. This controllable reusability extends the applications of nanotechnology and bioengineering, enhancing the practicality and efficiency of these circuits across various domains.

Analysis and Simulation of Current Balancer Circuit for Phase-Gain Correction of Unbalanced Differential Signals

The phase and gain imbalance of a balun output can be adjusted by a differential current balancer (DCB) circuit. The performance of DCB circuit, for correcting the phase (gain) imbalance, is analyzed for a wide range of input signal level, and the accuracy is verified with circuit simulation. To illustrate the phase-error/gain-error (PE/GE) correction, a 30–40[Formula: see text]GHz DCB circuit is designed and simulated in a 180-nm CMOS process. The DCB is examined for input PE, [Formula: see text], of [Formula: see text] and input GE, GA, of [Formula: see text][Formula: see text]dB. Analysis and simulation illustrate an output phase error [Formula: see text] of [Formula: see text] and output gain error [Formula: see text] of [Formula: see text][Formula: see text]dB, over frequency range of 20–50[Formula: see text]GHz. The results of DCB circuit for PE (GE) compensation are compared to that of phase-correction technique (PCT) circuit, illustrating the superior phase (gain) imbalance correction of the DCB circuit with lower NF and DC power consumption.

Integration mixer: An efficient mixed neural network for memory dynamic stability analysis in high dimensional variation space

In low-power designs, the SRAM performance suffers from the process variation. Statistical analysis for the yield of circuit block (e.g., static random-access memory) is extremely time-consuming due to the expensive simulations since the variation space is high-dimensional. In this paper, we construct a mixed neural network to substitute the simulation. We present Mixer. It mainly contains two types of layers: one with regularized sub-radial basis function networks (sub-RBFs) applied independently to extract the effects on circuit performance of the subsets of input process variables, and the other one with multi-layer perceptron (MLP) applied to learn the connection of these extracted effects. When trained with small datasets of high dimension generated from 28 nm memory circuits, our Mixer shows competitive accuracy and efficiency compared with other state-of-the-art models.*

Training-Free Quantum Architecture Search

Variational quantum algorithm (VQA) derives advantages from its error resilience and high flexibility in quantum resource requirements, rendering it broadly applicable in the noisy intermediate-scale quantum era. As the performance of VQA highly relies on the structure of the parameterized quantum circuit, it is worthwhile to propose quantum architecture search (QAS) algorithms to automatically search for high-performance circuits. Nevertheless, existing QAS methods are time-consuming, requiring circuit training to assess circuit performance. This study pioneers training-free QAS by utilizing two training-free proxies to rank quantum circuits, in place of the expensive circuit training employed in conventional QAS. Taking into account the precision and computational overhead of the path-based and expressibility-based proxies, we devise a two-stage progressive training-free QAS (TF-QAS). Initially, directed acyclic graphs (DAGs) are employed for circuit representation, and a zero-cost proxy based on the number of paths in the DAG is designed to filter out a substantial portion of unpromising circuits. Subsequently, an expressibility-based proxy, finely reflecting circuit performance, is employed to identify high-performance circuits from the remaining candidates. These proxies evaluate circuit performance without circuit training, resulting in a remarkable reduction in computational cost compared to current training-based QAS methods. Simulations on three VQE tasks demonstrate that TF-QAS achieves a substantial enhancement of sampling efficiency ranging from 5 to 57 times compared to state-of-the-art QAS, while also being 6 to 17 times faster.

Low thermal crosstalk silicon MZI optical switch with high speed and low power consumption

Abstract We developed a compact thermo-optic Mach–Zehnder interferometer switch with a direct heating heater using multimode interference and achieved a sufficiently low thermal crosstalk performance. Large-scale switch systems, such as optical neural networks, require thermo-optical switches with low power consumption, fast switching speed, compact size, and low thermal crosstalk. This switch is equipped with a heater that directly heats the Si core waveguide, which is a structure that connects non-doped Si wires between phase shifters and a heatsink. As a result, a significant miniaturization with a phase shifter length of approximately 7 μm, low π-phase shift power consumption of less than 20 mW, and fast switching in sub-microseconds were achieved. The improved phase shifter showed a very small figure of merit of 8.89 mW∙μs. Simultaneously, transmission spectrum measurements of nearby ring resonators show that the thermal crosstalk is significantly reduced even at a distance of only 30 μm. This device can contribute to the overall circuit performance and footprint reduction in large-scale optical integrated circuits and optical neural network configurations.

Beyond-adiabatic Quantum Admittance of a Semiconductor Quantum Dot at High Frequencies: Rethinking Reflectometry as Polaron Dynamics

Semiconductor quantum dots operated dynamically are the basis of many quantum technologies such as quantum sensors and computers. Hence, modelling their electrical properties at microwave frequencies becomes essential to simulate their performance in larger electronic circuits. Here, we develop a self-consistent quantum master equation formalism to obtain the admittance of a quantum dot tunnel-coupled to a charge reservoir under the effect of a coherent photon bath. We find a general expression for the admittance that captures the well-known semiclassical (thermal) limit, along with the transition to lifetime and power broadening regimes due to the increased coupling to the reservoir and amplitude of the photonic drive, respectively. Furthermore, we describe two new photon-mediated regimes: Floquet broadening, determined by the dressing of the QD states, and broadening determined by photon loss in the system. Our results provide a method to simulate the high-frequency behaviour of QDs in a wide range of limits, describe past experiments, and propose novel explorations of QD-photon interactions.

Design and optimization of spoof surface plasmon polaritons based multi-octave power amplifier using PSO algorithm

In this article, we explore how spoof surface plasmon polaritons (SSPP) theory can be applied to the design of active radio frequency (RF) power amplifiers (PAs). This work utilizes SSPP structures for the design of both input and output matching networks for a multi-octave PA. In order to perform proper impedance matching, the properties of SSPP unit structures are presented and analyzed. A description of the performance of the initial PA has been provided and discussed. Additionally, particle swarm optimization (PSO) is used to further enhance the performance of the PA circuit. In comparison with an embedded gradient method in a commercial tool, the PSO method results in a better optimization result. The fabricated PA is tested and the results indicate that in the frequency range of 0.5 GHz to 2.9 GHz, it achieves an output power of 40.4 dBm to 41.2 dBm, a power added efficiency of 60.5–65%, and an output gain exceeding 10 dB. Compared to recent work, the multi-octave PA in this work broadens bandwidth while maintaining high output power and PAE. To further verify the linearity of the SSPP-based PA, digital pre-distortion (DPD) is implemented. As a result of the DPD, the linearity of the SSPP PA was greatly enhanced.

Efficient 3’s Complement Circuit for Ternary-ALU

Carrying more information makes the ternary-computation effective in order to reduce the interconnect complexity and hence, ternary computer can be the future alternative to conventional (binary) counterpart. As a consequence the ternary arithmetic has become the centre of choice among circuit/system researcher in recent time. Ternary adder/subtractor is the integral part of Ternary Arithmetic Logic Unit (TALU) and the 3’s complement is used to represent negative ternary number in TALU. This work proposes a new two-step low hardware-cost strategy to converts ternary input into its 3’s complement output. Novel hardware optimization using normal process Enhancement-type Metal Oxide Semiconductor (E-MOS)-transistor is explored and exploited to design proposed 4-trit 3’s complement generator on 32nm standard CMOS technology with 0.9V supply-rail at 27°C temperature using typical MOS-transistor. Unbalanced ternary digit “0”, “1” and “2” are denoted with ground, supply/2 and supply respectively. The T-Spice transient simulations with all possible test patterns validate the working of proposed circuit and the corresponding speed-power characteristic is compared with most recent counterpart. The circuit performance is also evaluated with different load condition. The 4-trit 3’s complement circuit is extended next to propose 16-trit 3’s complement generator and the impact of Process and Environmental variation on the proposed circuit is studied.

High-Speed 16-Bit SAR-ADC Design at 500 MS/s with Variable Body Biasing for Sub-Threshold Leakage Reduction

In this study, a high-performance 16-bit, 500 MS/s successive approximation register analog-to-digital con-verter (SAR-ADC) with variable body biasing (VBB) for re-ducing sub-threshold leakage is designed and optimized. The suggested ADC architecture makes use of a voltage threshold complementary metal-oxide-semiconductor (VTCMOS) cir-cuit with Widlar current mirror technology to efficiently con-sume 39.2 μW at an operating voltage of 1.0 V. Notably, the optimized ADC achieves outstanding performance measures, such as a signal-to-noise and distortion ratio (SNDR) of 97 dB and a total harmonic distortion (THD) of -97.97 dB, which are crucial markers of the ADC's accuracy and fidelity. An over-view of the growing need for high-resolution ADCs in contem-porary high-speed data conversion systems opens the study. The main goal of this effort is to improve overall ADC per-formance and tackle the problem of sub-threshold leakage. The Widlar current mirror technology and the VTCMOS cir-cuit are integrated for enhanced linearity, decreased current mismatch errors, and minimized leakage current. This inte-gration is highlighted in the full explanation of the ADC de-sign. The advent of the VBB approach as a successful method of leakage reduction is a significant contribution to this re-search. The theoretical foundations and workings of the VBB technique are discussed, and thorough simulations and tests are used to assess how the VBB technique affects leakage cur-rent and circuit performance. The SAR-ADC design and simulations were carried out using Cadence Virtuoso soft-ware.

Revolutionizing Technology with Spintronics: Devices and Their Transformative Applications

The scaling of metal oxide semiconductor field effect transistors (MOSFETs) for data storing and logic circuit operation has reached a critical point, beyond which further scaling poses various secondary issues. These problems include short channel effects, hot carrier effects (HCEs), and reliability concerns. However, a promising alternative called spintronics has recently emerged as a highly exciting technology. Spintronics considers both the charge and spin of electrons in device operations and offers superior properties compared to MOSFETs.Researchers have reported numerous spintronics devices that exhibit significant potential in memory and logic circuits when integrated with complementary metal oxide semiconductor (CMOS) technology. These devices not only possess excellent scalability but also consume less power than MOSFETs at the nano-scale level. This article aims to provide a comprehensive review of the current state, future prospects, and challenges associated with spintronics devices.

The Development of a 2D Numerical Model of a Device Using the Elastocaloric Effect to Cool Electronic Circuits

The scientific community has been working hard lately to develop fresh, environmentally friendly refrigeration technologies. Those based on solid-state refrigerants are among the Not-In-Kind Refrigeration Technologies that show great promises. The one based on the elastoCaloric Effect is among the most interesting of them. This paper presents the development of a 2D numerical model for a device harnessing the elastocaloric effect with the primary objective of cooling electronic circuits. The study focuses on the intricate interplay between mechanical and thermal aspects, capturing the dynamic behavior of the elastocaloric material in response to cyclic mechanical loading. The numerical model incorporates detailed descriptions of the electronic circuits, accounting for heat dissipation and thermal management. Through simulations, the optimal configuration for efficient cooling is explored, considering various operative conditions and mechanical loading conditions (tensile and bending). The findings contribute to the advancement of elastocaloric cooling technology, offering insights into the design and optimization of devices aimed at enhancing electronic circuit performance through effective thermal control. The results that the most promising configuration is based on bending, a design choice resulting appropriate for cooling the electronic circuits.

Multiphoton imaging of hippocampal neural circuits: techniques and biological insights into region-, cell-type-, and pathway-specific functions.

The function of the hippocampus in behavior and cognition has long been studied primarily through electrophysiological recordings from freely moving rodents. However, the application of optical recording methods, particularly multiphoton fluorescence microscopy, in the last decade or two has dramatically advanced our understanding of hippocampal function. This article provides a comprehensive overview of techniques and biological findings obtained from multiphoton imaging of hippocampal neural circuits. This review aims to summarize and discuss the recent technical advances in multiphoton imaging of hippocampal neural circuits and the accumulated biological knowledge gained through this technology. First, we provide a brief overview of various techniques of multiphoton imaging of the hippocampus and discuss its advantages, drawbacks, and associated key innovations and practices. Then, we review a large body of findings obtained through multiphoton imaging by region (CA1 and dentate gyrus), cell type (pyramidal neurons, inhibitory interneurons, and glial cells), and cellular compartment (dendrite and axon). Multiphoton imaging of the hippocampus is primarily performed under head-fixed conditions and can reveal detailed mechanisms of circuit operation owing to its high spatial resolution and specificity. As the hippocampus lies deep below the cortex, its imaging requires elaborate methods. These include imaging cannula implantation, microendoscopy, and the use of long-wavelength light sources. Although many studies have focused on the dorsal CA1 pyramidal cells, studies of other local and inter-areal circuitry elements have also helped provide a more comprehensive picture of the information processing performed by the hippocampal circuits. Imaging of circuit function in mouse models of Alzheimer's disease and other brain disorders such as autism spectrum disorder has also contributed greatly to our understanding of their pathophysiology. Multiphoton imaging has revealed much regarding region-, cell-type-, and pathway-specific mechanisms in hippocampal function and dysfunction in health and disease. Future technological advances will allow further illustration of the operating principle of the hippocampal circuits via the large-scale, high-resolution, multimodal, and minimally invasive imaging.

Very high step‐down coupled inductor two‐phase buck converter with single magnetic element and inherent clamp voltage capability

AbstractThis paper proposed a new two‐phase high step‐down DC–DC converter is proposed. This converter is derived from the two‐phase series‐capacitor converter. The proposed converter replaces the series capacitor with a new structure that integrates Valley‐Fill circuit and coupled‐inductors concepts. This replacement can improve the voltage gain of the converter as well as a considerable reduction of diodes voltage stress. The proposed structure implements a dual‐phase buck using a single magnetic element. Also, the proposed structure inherently limits the voltage spikes due to the leakage inductance of coupled inductors without any additional clamp circuit. The proposed converter is analyzed, and design guidelines are provided. A 300–24 V prototype converter is implemented to justify the validity of circuit operation and the theoretical analysis.

Analog and Mixed-signal Integrated Circuits of 5Gand 6G Data Communication

The complex analog and mixed-signal transceivers where overall system performance is often limited by the weakest performing subsystem. While analog and mixed-signal integrated circuits have significantly advanced, the future of 5G and 6G transceiver design could be accelerated by including artificial intelligence. In this combination, analog integrated circuit design and operation would harness machine learning to identify, characterize, and act upon variations and anomalies in system performance. Focusing on 5G and 6G, this paper investigates solutions for a unified intelligent integrated transceiver: a conceptual combination of a traditional analog subsystem, a supporting digital subsystem that enables artificial intelligence, and dedicated feedback circuitry or sensors that monitor performance, efficiency, or reliability. Active and passive components and propagation channels are reviewed based on their merits of introducing intelligence. Holistically and for broader applicability, the paper conceptualizes and coins the notion of an ‘‘intelligent integrated system (IIS)’’, which brings forward a novel unified vision and approach toward context-aware subsystems that dynamically interact with ambient and varying operating conditions. To demonstrate viability, the paper concatenates a select set of measurement results.

Investigation of Temperature and Channel Dimension Effects on CMOS Circuit Performance

Investigation of Temperature and Channel Dimension Effects on CMOS Circuit Performance

Research and application of SiC _ MOSFETs in DC-DC circuit of new energy electric vehicle

In recent years, with the continuous optimization and improvement of power devices, various types of devices such as SiC _ MOSFETs, IGBTs, and Si _ MOSFETs have emerged in the market. Although the datasheets for these devices provide detailed descriptions of their device structures and electrical characteristics, there is a relative scarcity of specific application scenarios and corresponding simulation experimental data. This paper aims to comprehensively review recent research on the device structures and electrical characteristics of SiC _ MOSFETs, IGBTs, and Si _ MOSFETs. Additionally, we intend to conduct a systematic classification and comparative analysis to evaluate their performance in practical circuit applications. Furthermore, we have utilized MATLAB and Simulink to construct a representative simulation model of a DC-DC Buck-Boost circuit for new energy electric vehicles. Common SiC _ MOSFETs, IGBTs, and Si _ MOSFETs available in the market have been selected, and their parameters have been configured to match those in the simulation circuit. This approach enables us to explore the performance of these components in real-world circuit applications. Subsequently, the performance of these simulated circuits has been rigorously examined in practical scenarios. This comprehensive analysis provides a deeper understanding of the advantages of SiC _ MOSFETs compared to the other two devices and their potential contribution to the future development of electric vehicle technology. We anticipate that this research will drive advancements in electric vehicle technology and contribute to the realization of sustainable mobility.