Voltage Transfer Research Articles

Analysis and Optimization Design Scheme of CMOS Ultra-Wideband Reconfigurable Polyphase Filters on Mismatch and Voltage Loss

This manuscript presents an analysis and optimization scheme for the ultra-wideband passive reconfigurable polyphase filters (PPFs) to minimize I/Q (in-phase and quadrature-phase) phase/amplitude mismatch and voltage loss. By building a mathematical model of the voltage transfer, the relationship between the resonant frequency of each stage and the I/Q mismatch and the relationship between the network impedance and the voltage loss are revealed, providing a scheme for PPF optimization. The proof-of-concept 2~8 GHz wideband reconfigurable PPF is designed in a 55 nm CMOS process. The optimization scheme enables the designed PPF to achieve an I/Q phase mismatch within 0.2439° and an I/Q amplitude mismatch within 0.098 dB throughout the entire band, and it shows great robustness during Monte Carlo sampling. The maximum voltage loss is 17.7 dB, and the total chip area is 0.174 × 0.145 mm2.

Powering for Long Term Monitoring in the Enclosed Areas

Paper presents possible solution and practical examples for wireless powering and signal transfer using the inductive coupling. It can be suitable for long term monitoring in enclosed areas and systems that are isolated form the surroundings. This solution allows avoiding the batteries. It can be used for probes bricked in to the wall, extreme temperature environment measurement, the barrels internal shells health monitoring etc. Main advantage of this kind of powering is nearly unlimited lifetime, no toxic pollutions (such as Cd, Li, H2SO4,… contained in the batteries) and universal applicability. The powering is provided by the near magnetic field. The resonance is considered in the design for increasing the voltage transfer. Also the passive signal transfer can be performed using this principle while it is similar to the RFID systems (Radio Frequency Identification). The main contribution of this paper is prediction of the powering potentialities and distance limits of this strategy. Voltage levels, power transfer efficiency and signal modulation effects are studied up to distance of 30 cm. The simple coils are considered. Also special converter principle is presented for this purpose.

A High-Efficiency DC-DC Converter Based on Series/Parallel Switched Inductor Capacitors for Ultra-High Voltage Gains

A high-efficiency DC-DC converter employing a modified architecture called the hybrid switched inductor–capacitor series (MHSLCS) is proposed in this paper. The primary goal is to achieve a notably ultra-high voltage gain for renewable energy systems (RESs). Furthermore, the use of only one input capacitor in the MHSLCS eliminates pulsations in the input current at both low and high duty ratios. The proposed converter integrates the MHSLCS with a modified switched capacitor (MSC) that interleaves with the main MOSFET, effectively doubling the voltage transfer gain. Additionally, a modified hybrid switched inductor–capacitor parallel (MHSLCP) is incorporated in parallel with an interleaved auxiliary MOSFET. Both MOSFETs, combined with the MSC, contribute to achieving an ultra-high voltage gain. In addition, the inductors of the MHSLCP operate in a discontinuous conduction mode (DCM), which results in significant stress reductions in the power diodes and switches at high output voltages. The advantages of the proposed converter are multifaceted, demonstrating a high efficiency while minimizing the voltage in power device diodes and MOSFETs. The use of low inductance and capacitance values at high switching frequencies further enhances the performance. Wide-bandgap (WBG) power devices are employed to achieve the desired high voltage gain and efficiency. The proposed converter was designed with a PCB and underwent experimental testing to validate laboratory results. The proposed converter boosted the input voltage from 30 V to a variable output voltage between 325 V and 500 V, with a power output of 325 watts and an efficiency of 95.5%.

Development of high-gain switched-capacitor based bi-directional converter for electric vehicle applications

High efficiency, high voltage transfer ratio (VTR), and low input ripple current is required in any bidirectional DC-DC converter (BDC) that plays a major role in interfacing batteries in applications like dc microgrids and electric vehicles (EVs). For meeting these requirements, a switched capacitor-based BDC is proposed to interface the battery with a propulsion system via DC Link. It has a simple circuit with only a set of switching operations, High VTR, and lesser ripple current on the low voltage (LV) side are advantages of the proposed High Gain Switched-Capacitor Bi-directional DC-DC Converter (SC-BDC) making it appropriate for use in EVs. The steady-state analysis, design consideration of passive components, loss and efficiency analysis are presented. Finally, the proposed High Gain SC-BDC is compared with few of the existing BDC in the literature. The feasibility of the converter was demonstrated by simulating a 200 W converter and validating results produced in a MATLAB environment.

Study on Split-Capacitors Applied in Positive Output Super-Lift Luo-Converters

Voltage Lift Technique has been successfully employed in design of DC/DC converters, e.g. three series Luo-Converters. However, the output voltage increases in arithmetic progression. Super Lift Technique is the most significant contribution in Power Electronics, e.g. four series Super-Lift Converters. Their output voltage increases in geometric progression. This paper introduces a novel approach – Super Lift Technique Armed by Split Capacitors that implements the output voltage increasing in higher geometric progression. It effectively enhances the voltage transfer gain in power series as well.

High Efficiency Dual-Active-Bridge Converter with Triple-Phase-Shift Control for Battery Charger of Electric Vehicles

An optimal modulation scheme with triple-phase-shift (TPS) control could increase the efficiency in the entire load range for a dual-active-bridge (DAB) converter under wide output voltage range conditions. Therefore, this study proposes a convergent approach to TPS mode selection, coupled with an optimal modulation scheme, ensuring the circuit’s efficiency over the entire range in the realm of a high-power and high-efficiency battery charger for electric vehicles. The convergent approach to TPS mode selection also reduces the numerous cases for small-signal analysis through general average modeling. After verifying the small-signal models under various voltage transfer ratios and load conditions to verify the stability, a converter prototype with a rated power of 15 kW is built and tested. Thus, a peak efficiency of 97.7% can be achieved.

Dual‐input single‐output high step‐up DC–DC converter for renewable energy applications

AbstractThis paper introduces a dual‐input single‐output (DISO) non‐isolated DC–DC converter with the capability to accommodate multiple input ports. It supports both bidirectional and unidirectional power flows. The proposed converter employs the switched‐capacitors (SC) technique, resulting in a high‐ voltage transfer gain. Although the use of the SC technique leads to discontinuous input current, this issue has been addressed by incorporating an inductor at the input side. The DISO high‐voltage gain converter offers flexible control options, reduces current and voltage stress on semiconductors, and imposes no duty cycle limitations due to the proposed switching methods. Furthermore, when Port 2 fails, the proposed converter can transfer energy to the load by sources in Port 1 without interruption. The steady‐state model and small‐signal analysis (SSA) of the proposed converter are examined at continuous conduction mode (CCM). To evaluate accurately, the proposed converter is compared with the recently presented converters based on important characteristics. Additionally, a comprehensive power loss analysis is performed. Following the design specifications, an evaluation and testing of a prototype are conducted to verify the feasibility and performance of the converter.

Investigation on Germanium Transistors with HfOx-Based Gate Stacks for CMOS Operations

Germanium (Ge) FinFETs with HfOx-based gate stacks are fabricated to study the CMOS applications. To evaluate the logic circuit operation, the associated CMOS inverters are characterized. Compared to the HfO2, the Hf0.5Zr0.5Ox (HZO) gate stack provides higher drive currents and more symmetric Vth behaviors, which should be associated with the polarization effect. Through cyclic voltage transfer characteristic (VTC) operation and systematical analysis, it is found that both polarization and charge trapping in the gate stack impact the device characteristics. The HZO devices show a negative VTC shift with cycling, while the HfO2 devices reveal a positive shift. This opposite VTC behavior for both gate stack schemes indicates that the interaction of interface states and dipoles significantly influences the device operation. The results revealed in this work present a comprehensive understanding of HfOx-based device optimization.

A Comparative Analysis of VS-CNTFET and CMOS Based Inverter Circuit

This abstract delves into the comparative exploration between Carbon Nanotube Field Effect Transistors (CNTFETs) and traditional CMOS (Complementary Metal-Oxide-Semiconductor) transistors, with a specific emphasis on digital inverter circuits. Utilizing carbon nanotubes derived from the graphene allotrope, CNTFETs are introduced as a technological advancement, providing advantages such as reduced size and lower power consumption. The investigation centres on the evaluation of the Stanford model, particularly focusing on the Virtual Source Carbon Nanotube Field Effect Transistor. This specific model showcases superior performance, compact dimensions, and decreased power requirements when contrasted with silicon-based MOSFETs. The analytical process involves subjecting virtual source CNTFET inverter circuits and MOSFET-based circuits to testing via the Symica software tool, encompassing the examination of transient response, voltage transfer characteristics, and steady-state power consumption. The outcomes underscore the potential of CNTFETs as promising alternatives in the progression of digital design, offering heightened efficiency and diminished power consumption.

DFT based atomic modeling and temperature analysis on the RF and VTC curve of high-k dielectric layer-assisted NCFET

In this report, Density Functional Theory (DFT) based calculation using a Quantum Atomistic Tool Kit (ATK) simulator is done for the hafnia-based ferroelectric material. The band structure, projected density of states (PDOS), and Hartree potential (VH) are taken into account for hafnium oxide (HfO2) and silicon-doped hafnium oxide (Si-doped HfO2). Further, we analyze the temperature variation impact on analog parameters and voltage transfer characteristic (VTC) curve of inverter application of Modified Negative Capacitance Field-Effect-Transistor (NCFET) using the Visual Technology-Computer-Aided-Design (TCAD) simulator. The Modified NCFET structure enhances the DC parameters like leakage current (IOFF) and Subthreshold Swing (SS) compared to the conventional NCFET structure. With the temperature impact, the variation in the parameters of Modified NCFET is discussed at 250 K, 275 K, 300 K, 325 K, and 350 K like transconductance (gm), output conductance (gd), early voltage (VEA) shows the increment as we move from 250 K to 350 K. The short channel effects (SCEs) like Drain Induced Barrier Lowering (DIBL) and Subthreshold Swing (SS) decrease with the temperature fall at 32.98% and 34.74%, respectively. Further, the VTC curve, Noise Margin (NM), and propagation delay of Modified NCFET-based inverter are discussed with the impact of temperature. The propagation delay for the circuit decreased by 67.94% with the rise in the temperature. These factors show that the Modified NCFET-based inverter gives a fast switching performance at high temperatures.

The Efficiency Improvement of Track-Type Wireless Power Transmission Systems through Electromagnetic Finite Element Analysis

The original system, designed as a combination structure of a linear machine and a wireless power transmission transformer, was designed to overcome the limitations of the wired power supply method used for working robots and transportation equipment in existing smart factories, and improvements in magnetic coupling and power transfer efficiency are needed. In this work, we study the efficiency improvement of a system that can supply wireless power to track-type transportation equipment. For this purpose, electromagnetic properties such as magnetic equivalent resistance, inductance, magnetic coupling rate, and core loss are analyzed using the finite element method. In addition, the results of magnetic field finite element analysis are applied in electrical equivalent circuit modeling to analyze the voltage transfer ratio and input/output characteristics of a CLLC resonant converter designed for wireless power transmission. The efficiency improvements of the proposed model are verified through a comparison of experimental and simulation results after fabricating a prototype. From the results of this study, a more optimized wireless power transmission system design based on the analysis results from an electromagnetic perspective can be realized to improve the efficiency of wireless power transmission.

High voltage DC-DC converter with standalone application

<span lang="EN-US">Designing DC-DC converters involves many voltage lift techniques. These techniques have been encouraged for their credible advantages. Most voltage lifting methods are applied in many areas of automotive, motor drives, telecom and electronic welfare in military applications. Voltage lifting techniques are known for their high voltage transfer gain and high efficiency. Ultra-lift converter yields very high output transfer gain with geometric progression compared to other voltage lift techniques such as super lift converters and classical boost converters. It also offers reduced size and improved efficiency when compared. In this proposed method ultra-lift converter operation is analyzed with continuous conduction mode.</span>

Highly Efficient Dual-Buck Structured Buck–Boost AC–AC Converter With Versatile Identical Inverting/Noninverting Operations

Single-phase dual-buck ac-ac (DBAC) converters are gaining attention due to their intrinsic protection from shoot-through and open-circuit problems of conventional ac-ac converters. However, researches on DBAC converters are mainly concentrated around unipolar topologies. In a few developed bipolar topologies till date, the inverting buck-boost operations (for series voltage injection and step-variable frequency outputs) are inefficient and burdened by large voltage and current stresses ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">v_in + v_o</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i_in</i> + <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i_o</i> ) of switching devices and ripples of passive elements. In this article, an efficient dual-buck structured buck-boost ac-ac converter is proposed, with the following features: no voltage source shoot-through and inductor open-circuit problems, natural attainment of safe-commutation without additional protection circuitry or complex control, no need of PWM dead-times, and elimination of high-frequency conduction of MOSFET's body diodes and related slow reverse recovery issues. The proposed converter provides distinct type efficient inverting and non-inverting buck (EINIBu) and boost (EINIBo) operations, with smaller switch voltage/current stresses ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">v_in</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">v_o</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i_in</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i_o</i> ) and passive component ripples. Combined inverting and non-inverting buck-boost (CINIBB) operations are also proposed with separate tuning of buck and boost voltage transfer ratios. A simple adaptable switching strategy provides the switch control pulses for all circuit operations by modulating the buck and boost control reference signals. The proposed converter provides sustained input/output currents and performs well with non-resistive loads. Extensive theoretical analysis is presented followed by practical verifications on a 400-VA laboratory circuit.

Ultra‐high voltage gain DC–DC converter based on new interleaved switched capacitor inductor for renewable energy systems

SummaryIn this paper, introduces a DC–DC converter design based on a modified hybrid switched inductor‐switched capacitor architecture, aimed at achieving ultra‐high voltage gain in renewable energy systems (RES). The proposed converter involves adding a modified boosting conversion mode (MBM) that interleaves with the main switch to double the voltage transfer gain. Additionally, a modified switched capacitor (MSC) technique, utilizing two diodes as interleaved components, is integrated into the main and auxiliary switches to verify low voltage stress across them. In addition, modified hybrid switched inductors with capacitors (MSIC) and diodes are employed to validate ultra‐high voltage gain. The main advantages of the proposed converter are its high efficiency, low voltage stress across diodes and MOSFETs, and the utilization of low values of inductors and capacitors at high switching frequencies. In addition, the voltage stress across the inductors of the (MSIC) is reduced as the duty cycle increases. Furthermore, the current stress on the main switch is reduced when the charge of capacitor C1 becomes zero. Mathematical models for both continuous conduction mode (CCM) and discontinuous conduction mode (DCM) of the proposed converter are explored. Furthermore, a dual PI controller is designed for the proposed converter to maintain a high fixed output voltage. In addition, the PCB design and experimental testing of the proposed converter to verify the simulation and laboratory results. Specifically, the proposed converter is designed to boost up voltage (30–40 V) to a variable output voltage between 200 and 300 V at 300 W at efficiency 96.7%.

A new digital background calibration technique for pipeline analog to digital converters using decision points of the voltage transfer characteristics

A new digital background calibration technique for pipeline analog to digital converters using decision points of the voltage transfer characteristics

Effects of metal work function and gate-oxide dielectric on super high frequency performance of a non-align junction DG-MOSFET based inverter in the sub-100 nm regime: a TCAD simulation analysis

ABSTRACT This paper presents simulation analysis of an inverter made from non-aligned double gate field effect transistors (NADGFETs) in Sub-100 nm regime. The inverter consists of n-channel NADGFET and p-channel NADGFET device with a channel length of 40 nm and 50% non-alignment between gate and source/drain. The response of the inverter was tested by a combination of gate dielectric constant (k) and metal work function (ϕ). Three gate dielectrics namely, SiO2 (k = 3.9), Si3N4 (k = 7.2), HfO2 (k = 24), and three metal work function namely tungsten (ϕ = 4.5 eV), molybdenum (ϕ = 4.75 eV), gold (ϕ = 5 eV), were considered in the NADGFET inverter. This paper defines a kϕ index as characterising parameter to explore the best response from inverter configuration with minimum propagation delay, and minimum power consumption at super-high frequency. The paper proposes to analyse the NADGNFET device, in term of ION current, ION/IOFF ratio, cut-off frequency, and gate delay. And observes that low k material with moderate metal work function gives best response. The work then simulates the inverter and group the results into voltage transfer curve (VTC), transient response, and power dissipation category. The result shows that when inverter was subjected to high frequency, all the kϕ combination responds good, however when the inverter was subjected to super-high frequency, the low value of kϕ combination performs well. Thus, the result concludes that SiO2-M2 combination will be best selection to get minimum propagation delay and dynamic power dissipation by the inverter. The test strategy presented in this paper on the basis of kϕ index can serve as benchmark to test inverter device at super-high frequency.

ОСОБЛИВОСТІ ЗМІНИ РОБОЧИХ СТАНІВ ВИКОНАВЧИХ СТРУКТУР БАГАТОРІВНЕВИХ ВИПРЯМЛЯЧІВ

The main component of DC power supply systems are various semiconductor mostly controlled rectifiers with corresponding filter capacitors. In particular, these are multi-level rectifiers (MLRs) with a purposeful discrete-time change in the voltage transfer coefficient through a corresponding change in the operating state of its executive structure. Synthesized optimal variants of these structures are characterized by the high efficiency of the use of semiconductor switches elements. The work revealed and analyzed the peculiarities of the implementation of transitions between the specified operating states in two types of MLR – with a wide (full) and with a limited range of output voltage regulation. Taking into account these features made it possible to determine appropriate algorithms for discrete-time control of semiconductor switches elements of the MLR, which ensure an acceptable course of these transitions, during which the possibility of noticeable unwanted surges or drops in the voltage supplied to the consumer is practically excluded. The multivariate implementation of the algorithms for transitions between the output voltage levels of the MLR is another aspect of the multivariate transformer-and-switches executive structures of converters in general. References 10, tables 1, figures 5.

Impact of Parametric Variation on the Characteristics and Performance of CNTFET Inverter

In this paper, a simple carbon nanotube field effect transistor (CNTFET)-based inverter has been simulated and the impacts of changing various design and process parameters on its characteristics and performance have been analysed using HSPICE. The 32 nm CNTFET model of Stanford University has been used here for the simulation of the inverter. The simulation results and the voltage transfer characteristics (VTC) curve of the inverter have been extracted for (i) different channel lengths, (ii) top gate di-electric material thickness (tox), (iii) pitch value (iv) the number of tubes in CNTFET channel region and (v) chirality of the CNT. It has been observed that the VTC curve changes significantly with different values of these parameters. Some important output parameters like maximum dc current, power, rise time, fall time, average propagation delay, etc. have been measured in each case. Changes in maximum power consumption value due to the change in different parameter values are observed through plotted graphs. Output dc current vs. input voltage graphs have been plotted for different chirality of the tubes, the number of the tubes, and pitch values between n-type CNTFET and p-type CNTFET of the inverter.

Design of Binary and Ternary Logic Inverters Based on Silicon Feedback FETs Using TCAD Simulator

A feedback field effect transistor (FBFET) with p-n-p-n structure benefits from a positive feedback mechanism. In this structure, the accumulated charges in its potential well and limitation of carrier flow by its internal potential barrier lead to superior electrical properties such as lower subthreshold swing (SS) and higher I ON / I OFF ratio in comparison with FinFET. Thus, FBFET is a promising alternative for digital applications such as logic inverters. In this paper, binary and ternary logic inverters are designed by using FBFETs with 40 nm channel length. The doping profile in the device plays an essential role and specifies the binary or ternary operation of the inverter. The inverter is analyzed by using a TCAD mixed-mode simulator. The results indicate the high value of 1010 for I ON / I OFF ratio with an extremely low SS (1 mV/decade). The voltage transfer characteristics of the inverter and its dependence on doping levels have been investigated. Also, the electrical properties of this inverter are compared with previous inverter counterparts.

Double Coupling In-Wheel IPT System for Electric Vehicles

The electric automotive industry revolutionizes the transportation sector with new disruptive technologies like wireless charging systems and the tire industry is no exception. New airless and sustainable tire designs offer new possibilities to embody wireless charging technologies. This paper presents a novel in-Wheel Inductive Power Transfer (inWIPT) batteries charger design for electric vehicles (EV). The proposed system uses two magnetic couplers (MC) to transfer the energy: one from the off-board side to the wheel and another from the wheel to the on-board side. The proposed configuration keeps the air gap between the off-board transmitter pad and the wheel receiver to a minimum and almost independent of the vehicle type (Sedan, Suv, Truck). The two MCs are connected by a new resonant tank which modifies the voltage transfer characteristics. A step by step methodology that identifies the operational range of the mutual inductances, based on certain design specifications and constraints, is also presented. Experimental results validate the proposed inWIPT in a quasi load independent voltage operation in different coupling charging scenarios and a maximum output power of 2.6 kW with an efficiency of 89.3 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\%$</tex-math></inline-formula> .