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ZERO-CURRENT AND ZERO-VOLTAGE SWITCHING PWM BOOST FULL-BRIDGE CON VERTER 被引量:1
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作者 周林泉 阮新波 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第1期60-66,共7页
This paper proposes a zer o current and zero voltage switching (ZCZVS) PWM Boost full bridge (FB) conve rter. With series inductors, the leading switches can realize zero current swit ching (ZCS) in a wide load ra... This paper proposes a zer o current and zero voltage switching (ZCZVS) PWM Boost full bridge (FB) conve rter. With series inductors, the leading switches can realize zero current swit ching (ZCS) in a wide load range using the energy of the output capacitor. Ma king use of parasitic capacitors of the lagging switches and parallel auxiliary i nductance with the primary winding of the transformer, the lagging switches can realize zero voltage switching (ZVS) under any load. Compared with the ZCS PWM Boost FB converter, the new converter has no current duty cycle loss. Operat ional principle and parameter design are analyzed. Experimental results verify the effectiveness of the proposed converter. 展开更多
关键词 pulse width modulation (PWM) soft switching boost converter full bridge converter zero voltage s witching zero current switching
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Physical Origin of Current-Induced Switching Angle Shift in Magnetic Heterostructures
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作者 Xiaomiao Yin Guanglei Han +3 位作者 Guowen Gong Jun Kang Changmin Xiong Lijun Zhu 《Chinese Physics Letters》 2025年第11期238-243,共6页
Accurate quantification of the spin–orbit torques(SOTs) is critical for the identification and applications of new spin-orbitronic effects. One of the most popular techniques to quantify the SOTs is the “switching a... Accurate quantification of the spin–orbit torques(SOTs) is critical for the identification and applications of new spin-orbitronic effects. One of the most popular techniques to quantify the SOTs is the “switching angle shift”, where the applied direct current is assumed to shift, via domain wall depinning during anti-domain expansion, the switching angle of a perpendicular magnetization in a linear proportional manner under a large rotating magnetic field. Here, we report that, for the most commonly employed perpendicular magnetization heterostructures in spintronics(e.g., those based on FeCoB, Co, and Co/Ni multilayers), the switching angle shift considerably misestimates the SOT within the domain wall depinning analysis of the slope of linear-in-current scaling and may also have a non-zero residual value at zero direct current. Our experiments and simulations unveil that the switching angle shift is most likely dominated by chiral asymmetric nucleation rather than expansion of anti-domains. The in-plane field from external magnets and current-induced SOTs lowers the perpendicular nucleation field and thus reduces the required switching angle, ultimately leading to an underestimation of SOTs by domain wall depinning analysis. These results have advanced our understanding of magnetization switching in spintronic devices. 展开更多
关键词 switching angle shift spin orbit torques sots domain wall depinning large rotating magnetic field applied direct current magnetic heterostructures spin orbit torques perpendicular magnetization
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Simplified Model Predictive Current Control for Dual Three-phase PMSM with Low Computation Burden and Switching Frequency 被引量:1
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作者 Huawei Zhou Xiaolong Xiang +1 位作者 Yibo Li Tao Tao 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第4期447-454,共8页
Finite-control-set model predictive control(FCSMPC)has advantages of multi-objective optimization and easy implementation.To reduce the computational burden and switching frequency,this article proposed a simplified M... Finite-control-set model predictive control(FCSMPC)has advantages of multi-objective optimization and easy implementation.To reduce the computational burden and switching frequency,this article proposed a simplified MPC for dual three-phase permanent magnet synchronous motor(DTPPMSM).The novelty of this method is the decomposition of prediction function and the switching optimization algorithm.Based on the decomposition of prediction function,the current increment vector is obtained,which is employed to select the optimal voltage vector and calculate the duty cycle.Then,the computation burden can be reduced and the current tracking performance can be maintained.Additionally,the switching optimization algorithm was proposed to optimize the voltage vector action sequence,which results in lower switching frequency.Hence,this control strategy can not only reduce the computation burden and switching frequency,but also maintain the steady-state and dynamic performance.The simulation and experimental results are presented to verify the feasibility of the proposed strategy. 展开更多
关键词 Computation time current increment vector Dual three-phase permanent magnet synchronous motor(DTPPMSM) Model predictive current control(MPCC) switching frequency
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Faster vortex core switching with lower current density using three-nanocontact spin-polarized currents in a confined structure
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作者 Hua-Nan Li Zhong Hua Dong-Fei Li 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期449-453,共5页
We perform micromagnetic simulations on the switching of magnetic vortex core by using spin-polarized currents through a three-nanocontact geometry. Our simulation results show that the current combination with an app... We perform micromagnetic simulations on the switching of magnetic vortex core by using spin-polarized currents through a three-nanocontact geometry. Our simulation results show that the current combination with an appropriate current flow direction destroys the symmetry of the total effective energy of the system so that the vortex core can be easier to excite,resulting in less critical current density and a faster switching process. Besides its fundamental significance, our findings provide an additional route to incorporating magnetic vortex phenomena into data storage devices. 展开更多
关键词 magnetic vortex core polarity switching spin-polarized current micromagnetic simulations
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Dependence of Switching Current Distribution of a Current-Biased Josephson Junction on Microwave Frequency
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作者 翟计全 李永超 +5 位作者 史建新 周渝 李小虎 许伟伟 孙国柱 吴培亨 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期118-121,共4页
We investigate the distribution of the switching current of a current-biased Josephson junction (CBJJ) and its dependence on the microwave frequency using two theoretical methods, one of which is the quantum traject... We investigate the distribution of the switching current of a current-biased Josephson junction (CBJJ) and its dependence on the microwave frequency using two theoretical methods, one of which is the quantum trajectory method and the other is the master equation method. Both the methods show that the distribution of the switching current of CBJJ will exhibit double peaks in a certain range of microwave frequency if proper microwave power is given, and the gap between the two peaks will increase with the microwave frequency. The obtained results can be used to identify the energy difference of the ground and first excited states in a Josephson junction for any bias current. 展开更多
关键词 Dependence of switching current Distribution of a current-Biased Josephson Junction on Microwave Frequency
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Transitional Recovery Voltages at Capacitive Currents Switching-off by Vacuum and SF6 Circuit-Breakers
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作者 Tahir M. Lazimov Samir V. Imanov Esam A. Saafan 《Journal of Energy and Power Engineering》 2012年第5期777-783,共7页
Results of calculation the recovery voltages conditioned by capacitive currents switching-off by high voltage vacuum and auto-compression (SF6) circuit-breakers are presented in the article. The purpose of research ... Results of calculation the recovery voltages conditioned by capacitive currents switching-off by high voltage vacuum and auto-compression (SF6) circuit-breakers are presented in the article. The purpose of research was evaluating the maximum values of recovery voltages and also studying the dependence of recovery voltages on some influencing factors, especially on type of circuit-breaker presented in numerical models with its dielectric strength restoration law, chopping current and operation time. The research was carried out with using computer simulation. 展开更多
关键词 Recovery voltages capacitive currents switching overvoltages capacitor banks dielectric strength restoration law.
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Constant Ripple Current Control for Switching DC-DC Converter
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作者 Gwo-Tarng Chern Jenn-Jong Shieh 《Journal of Energy and Power Engineering》 2012年第9期1437-1441,共5页
The adapted DC-DC converters should be smaller in size and have a small output current ripple to meet the increasing demand for low voltages with high performance and high density micro processors for several microele... The adapted DC-DC converters should be smaller in size and have a small output current ripple to meet the increasing demand for low voltages with high performance and high density micro processors for several microelectronic load applications. This paper proposes a DC-DC converter using variable on-time and variable switching frequency control enhanced constant ripple current control and reduced magnetic components. The proposed converter is realized by making the turn-offtime proportional to the on-time of the converter, according to the input and output voltage, thereby reducing the corresponding current ripple on output voltage in the continuous conduction mode. A Buck DC-DC converter using the proposed control strategy is analyzed in detail, along with some experimental results to show the performance and effectiveness of this converter. 展开更多
关键词 Constant ripple current DC-DC converter variable switching frequency continuous conduction mode indirect currentsensor magnetic component.
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A NEW SOFT-SWITCHING PUSH-PULL THREE-LEVEL CONVERTER 被引量:4
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作者 马运东 阮新波 严仰光 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期127-133,共7页
The application areas of conventional push pull converters are limited because of high voltage stress of switches (twice of input voltage). This paper presents a novel zero voltage and zero current switching (ZCS)... The application areas of conventional push pull converters are limited because of high voltage stress of switches (twice of input voltage). This paper presents a novel zero voltage and zero current switching (ZCS) PWM push pull three level converter in which the voltage stress of switches is input voltage. With phase shifted modulation strategy, the leading switches can only realize zero voltage switching (ZVS), and the lagging switches can realize ZCS when block capacitor and block diodes are added. Using the strategy, the converter overcomes the drawbacks presented by the conventional push pull converter, such as magnetic aberration, large switch loss, and voltage spike on switches, so it can get higher efficiency, and a wider application area. The operating principle of the new converter is analyzed and verified on a 600 W, 50 kHz experimental prototype. Several zero voltage and zero current switching PWM push pull three level converters are proposed. 展开更多
关键词 zero voltage and zero current switching push pull converter three levels
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Nonlinear Auto-Companding Method for Behavioral Modeling of Switched-Current Circuits
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作者 王伟 曾璇 +2 位作者 陶俊 苏仰峰 唐璞山 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第12期1254-1261,共8页
A wavelet collocation method with nonlinear auto companding is proposed for behavioral modeling of switched current circuits.The companding function is automatically constructed according to the initial error distri... A wavelet collocation method with nonlinear auto companding is proposed for behavioral modeling of switched current circuits.The companding function is automatically constructed according to the initial error distribution obtained through approximating the input output function of the SI circuit by conventional wavelet collocation method.In practical applications,the proposed method is a general purpose approach,by which both the small signal effect and the large signal effect are modeled in a unified formulation to ease the process of modeling and simulation.Compared with the published modeling approaches,the proposed nonlinear auto companding method works more efficiently not only in controlling the error distribution but also in reducing the modeling errors.To demonstrate the promising features of the proposed method,several SI circuits are employed as examples to be modeled and simulated. 展开更多
关键词 wavelet collocation method behavioral modeling switched current circuits nonlinear auto companding
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Resistive switching characteristics of Ti/ZrO_2/Pt RRAM device 被引量:2
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作者 雷晓艺 刘红侠 +5 位作者 高海霞 杨哈妮 王国明 龙世兵 马晓华 刘明 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期507-511,共5页
In this paper, the bipolar resistive switching characteristic is reported in Ti/ZrO2/Pt resistive switching memory de- vices. The dominant mechanism of resistive switching is the formation and rupture of the conductiv... In this paper, the bipolar resistive switching characteristic is reported in Ti/ZrO2/Pt resistive switching memory de- vices. The dominant mechanism of resistive switching is the formation and rupture of the conductive filament composed of oxygen vacancies. The conduction mechanisms for low and high resistance states are dominated by the ohmic conduc- tion and the trap-controlled space charge limited current (SCLC) mechanism, respectively. The effect of a set compliance current on the switching parameters is also studied: the low resistance and reset current are linearly dependent on the set compliance current in the log-log scale coordinate; and the set and reset voltage increase slightly with the increase of the set compliance current. A series circuit model is proposed to explain the effect of the set compliance current on the resistive switching behaviors. 展开更多
关键词 resistive random access memory (RRAM) resistive switching (RS) conductive filament (CF) compliance current
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A novel superjunction MOSFET with improved ruggedness under unclamped inductive switching 被引量:1
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作者 任敏 李泽宏 +5 位作者 邓光敏 张灵霞 张蒙 刘小龙 谢加雄 张波 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期612-618,共7页
The ruggedness of a superjunction metal-oxide semiconductor field-effect transistor (MOSFET) under unclamped inductive switching conditions is improved by optimizing the avalanche current path. Inserting a P-island ... The ruggedness of a superjunction metal-oxide semiconductor field-effect transistor (MOSFET) under unclamped inductive switching conditions is improved by optimizing the avalanche current path. Inserting a P-island with relatively high doping concentration into the P-column, the avalanche breakdown point is localized. In addition, a trench type P+ contact is designed to shorten the current path. As a consequence, the avalanche current path is located away from the N+ source/P-body junction and the activation of the parasitic transistor can be effectively avoided. To verify the proposed structural mechanism, a two-dimensional (2D) numerical simulation is performed to describe its static and on-state avalanche behaviours, and a method of mixed-mode device and circuit simulation is used to predict its performances under realistic unclanlped inductive switching. Simulation shows that the proposed structure can endure a remarkably higher avalanche energy compared with a conventional superjunction MOSFET. 展开更多
关键词 avalanche current path unclamped inductive switching SUPERJUNCTION MOSFET
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A New Switching Sequences of SVPWM for Six-Phase Induction Motor with Features of Reduced Switching Losses 被引量:9
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作者 Shaikh Mohammed Suhel Rakesh Maurya 《CES Transactions on Electrical Machines and Systems》 CSCD 2021年第2期100-107,共8页
In this paper,new SVPWM switching sequences for six-phase asymmetrical induction motor drives are derived with the aim to reduce inverter’s switching losses.Total three switching sequences are introduced in this pape... In this paper,new SVPWM switching sequences for six-phase asymmetrical induction motor drives are derived with the aim to reduce inverter’s switching losses.Total three switching sequences are introduced in this paper.These sequences are derived such that the phases get continuously clamped when a current of the phases is around its peak magnitude and hence reduced switching losses are recorded.The comparative performances of these modulation techniques are studied with two existing switching sequences.Simulation,analytical and experimental results are presented.Based on these results,it is found that new switching sequences reduce switching losses effectively in dual three phase inverters. 展开更多
关键词 Six-phase asymmetrical induction motor stator current distortion SVPWM and switching loss
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A Novel Crowbar Impulse Current Circuit for Testing the Switch-Type SPD 被引量:1
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作者 姚学玲 陈景亮 孙伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第2期221-226,共6页
A crowbar impulse current circuit for testing the switch-type surge protective device (SPD) is presented. The crowbar circuit consists of a computer control circuit, a trigger voltage pulse generator, a main dischar... A crowbar impulse current circuit for testing the switch-type surge protective device (SPD) is presented. The crowbar circuit consists of a computer control circuit, a trigger voltage pulse generator, a main discharging switch, and a crowbar pseudospark switch. The active trigger technology was studied in the crowbar impulse current circuit. The circuit monitors the main discharging current and generates a trigger signal at a proper time for the crowbar pseudospark switch operation. The trigger characteristics of the main discharge switch and the crowbar pseu- dospark switch were investigated. By monitoring the preset applied capacitor voltage, the gap distance of the main discharging switch could be adjusted to ensure a discharging delay time less than 2 μs. Equipped with a surface ttashover trigger device made of high relative perimittivity dielectric material BaTiO3 (εr = 3460), the discharge delay time of the crowbar pseudospark switch is less than 85 ns, and the minimum operating voltage is less than 1% of its self-breakdown voltage. With a storage capacitor of 9 μF , an inductor of 18 μH and a crowbar pseudospark switch, a load of 30 mΩ and an applied capacitor voltage of 40 kV, an impulse current waveform of maximum 25 kA was generated with a rise time and time to half peak value of 17.2 μs and 336μs respectively. 展开更多
关键词 crowbar impulse current circuit triggered crowbar pseudospark switch activetrigger technology switch-type surge protective device
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Study of the Fast-Closing Switch Used for Fault Current Limiters in Power System 被引量:1
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作者 邹积岩 董恩源 陈金祥 《Journal of Shanghai University(English Edition)》 CAS 2002年第1期92-96,共5页
This paper presents a new type of fault current limiter (FCL) based on fast closing switch, which is composed of a capacitor bank and a reactor in series. The main control component is a fast closing switch connecte... This paper presents a new type of fault current limiter (FCL) based on fast closing switch, which is composed of a capacitor bank and a reactor in series. The main control component is a fast closing switch connected in parallel with the capacitors, which is driven by the electromagnetic repulsion force. It can response the order within 1 ms. When fault occurs, the switch closes and the capacitors are bypassed, and the fault current is limited by the reactor. Simulation analysis and experiment show that the electromagnetic repulsion force actuator can meet the demand of fast closing switch, it is feasible to develop the FCL with low cost and high reliability. 展开更多
关键词 fault current limiter (FCL) electromagnetic repulsion force fast closing switch simulation.
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Analysis of Horizontal Block Stripe in TFT-LCD Panel in Switching-off Process 被引量:1
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作者 LU Lin-lin XU Shuai 《液晶与显示》 CAS CSCD 北大核心 2011年第4期464-468,共5页
The horizontal block stripe,as an image quality defect,was analyzed by means of output signals and bias voltage stress(BVS)test.The results showed that the defect was correlated with discharging efficiency.Further,two... The horizontal block stripe,as an image quality defect,was analyzed by means of output signals and bias voltage stress(BVS)test.The results showed that the defect was correlated with discharging efficiency.Further,two approaches were proposed,one was to improve TFT characteristic,the other was to add reset function.The combined experiments indicated that discharging promotion can improve the defect.Especially the latter is most optimal to eliminate the phenomenon. 展开更多
关键词 horizontal block stripe DISCHARGE switch off bias voltage stress drain current
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DESIGN OF TERNARY CURRENT-MODE CMOS CIRCUITS BASED ON SWITCH-SIGNAL THEORY 被引量:4
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作者 吴训威 邓小卫 应时彦 《Journal of Electronics(China)》 1993年第3期193-202,共10页
By applying switch-signal theory, the interaction between MOS transmission switch-ing transistor and current signal in current-mode CMOS circuits is analyzed, and the theory oftransmission current-switches which is su... By applying switch-signal theory, the interaction between MOS transmission switch-ing transistor and current signal in current-mode CMOS circuits is analyzed, and the theory oftransmission current-switches which is suitable to current-mode CMOS circuits is proposed. Thecircuits, such as ternary full-adder etc., designed by using this theory have simpler circuit struc-tures and correct logic functions. It is confirmed that this theory is efficient in guiding the logicdesign of current-mode CMOS circuits at switch level. 展开更多
关键词 switch-signal THEORY THEORY of transmission current-switches Multivalued LOGIC current-MODE CMOS CIRCUIT
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High-power High-efficient and Simplified High-frequency Switching Power Supply for Electrolytic Plating 被引量:6
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作者 MA Fujun LUO An XIAO Huagen 《中国电机工程学报》 EI CSCD 北大核心 2012年第21期I0001-I0022,共22页
针对大功率电解电镀开关电源的输入整流级引起的无功和谐波等电能质量问题,研究了一种基于高效PWM整流的高频开关电源。该电源前级整流器仅用4个开关管来进行PWM整流,后级采用半桥逆变器进行高频变换,显著减少了开关数量。针对三相四开... 针对大功率电解电镀开关电源的输入整流级引起的无功和谐波等电能质量问题,研究了一种基于高效PWM整流的高频开关电源。该电源前级整流器仅用4个开关管来进行PWM整流,后级采用半桥逆变器进行高频变换,显著减少了开关数量。针对三相四开关PWM整流器,推导一种基于开关模型的无差拍控制方法,该方法可实现系统的快速、无差整流。针对多台开关电源的并联均流问题,提出一种基于虚拟阻抗的自均流控制方法,可实现多台电源的均流稳定运行。通过仿真与实验验证了所提结构和控制方法的正确性。 展开更多
关键词 高频开关电源 电镀电源 电解 PWM整流器 高功率 半桥式逆变器 电能质量 HSPS
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Switching Impulse Strength of ±800 kV UHVDC Transmission Line Air Gap Insulation Under High Altitude Condition 被引量:3
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作者 LIAO Yongli GAO Chao +2 位作者 LI Ruihai WANG Guoli MA Yi 《高电压技术》 EI CAS CSCD 北大核心 2012年第12期3161-3165,共5页
关键词 高压直流输电线路 缺口冲击强度 空气间隙 绝缘特性 开关脉冲 高海拔 伏特 平面布置
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Analysis and Simulation on Current Commutation of DC Transfer Switches in UHVDC Transmission Systems 被引量:1
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作者 PENG Chang WEN Jialiang MA Guohua WANG Xiuhuan LIU Zhigang YU Kunshan 《中国电机工程学报》 EI CSCD 北大核心 2011年第36期I0001-I0001,共1页
关键词 高压直流输电系统 转换开关 仿真 换流 操作模式 电流
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A Design of the Elliptic Switched Current Filter
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作者 Zhu Da-bin Huang Tian-xi +1 位作者 Yao Yong-gang Su Yu-bei 《Wuhan University Journal of Natural Sciences》 CAS 1999年第2期39-43,共5页
In conformity with a fifth order RLC elliptic filter circuit prototype, it is easy to conceive the corresponding RC active filter circuit. Simple and feasible method presented here can be used to contrive... In conformity with a fifth order RLC elliptic filter circuit prototype, it is easy to conceive the corresponding RC active filter circuit. Simple and feasible method presented here can be used to contrive the equivalent switched capacitor filter circuit and switched current filter circuit. Consulting the technique data manual, we can expediently design a specific RLC filter. Therefore, it is of great convenience to design the switched current filter, which has the same performances. Such a kind of technology is useful in the domain of analogue sampled data signal processing. 展开更多
关键词 switched current switched capacitor active RC elliptic filter
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