The low voltage substrate current （Ib） has been studied based on generation kinetics and used as a monitor of interface states （Nit） generation for ultra-thin oxide n-MOSFETs under constant voltage stress. It is f...The low voltage substrate current （Ib） has been studied based on generation kinetics and used as a monitor of interface states （Nit） generation for ultra-thin oxide n-MOSFETs under constant voltage stress. It is found that the low voltage Ib is formed by electrons tunnelling through interface states, and the variations of Ib（△Ib） are proportional to variations of Nit （△Nit）. The Nit energy distributions were determined by differentiating Nit（Vg）. The results have been compared with that measured by using gate diode technique.展开更多
无线电能传输(wireless power transfer,WPT)系统具有安全、可靠、方便等优点。文章在分析WPT系统锂离子电池内阻及其典型充电方式的基础上,通过对WPT原理和谐振拓扑结构的研究,提出了基于LCC-S补偿式谐振拓扑的WPT系统。在电池等效负...无线电能传输(wireless power transfer,WPT)系统具有安全、可靠、方便等优点。文章在分析WPT系统锂离子电池内阻及其典型充电方式的基础上,通过对WPT原理和谐振拓扑结构的研究,提出了基于LCC-S补偿式谐振拓扑的WPT系统。在电池等效负载变化的情况下,通过合理的参数设计,LCC-S补偿式谐振拓扑结构可以分别实现与负载无关的恒流模式和恒压模式,无需切换拓扑结构。在理论分析的基础上,设计了系统的参数,并通过MATLAB仿真系统搭建仿真模型,验证了研究中的恒流模式和恒压模式。展开更多
A new insight into the constant current-constant voltage (CC-CV) charge protocol based on the spherical diffusion model was presented. From the model,the CV-charge process compensates,to a large extent,the capacity lo...A new insight into the constant current-constant voltage (CC-CV) charge protocol based on the spherical diffusion model was presented. From the model,the CV-charge process compensates,to a large extent,the capacity loss in the CC process,and the capacity loss increases with increasing the charging rate and decreases with increasing the lithium-ion diffusion coefficient and using a smaller τ value (smaller particle-size and larger diffusion coefficient) and a lower charge rate will be helpful to decreasing the capacity loss. The results show that the CC and the CV charging processes,in some way,are complementary and the capacity loss during the CC charging process due to the large electrochemical polarization can be effectively compensated from the CV charging process.展开更多
Threshold voltage (V<sub>TH</sub>) is the most evocative aspect of MOSFET operation. It is the crucial device constraint to model on-off transition characteristics. Precise V<sub>TH</sub> value...Threshold voltage (V<sub>TH</sub>) is the most evocative aspect of MOSFET operation. It is the crucial device constraint to model on-off transition characteristics. Precise V<sub>TH</sub> value of the device is extracted and evaluated by several estimation techniques. However, these assessed values of V<sub>TH</sub> diverge from the exact values due to various short channel effects (SCEs) and non-idealities present in the device. Numerous prevalent V<sub>TH</sub> extraction methods are discussed. All the results are verified by extensive 2-D TCAD simulation and confirmed through analytical results at 10-nm technology node. Aim of this research paper is to explore and present a comparative study of largely applied threshold extraction methods for bulk driven nano-MOSFETs especially at 10-nm technology node along with various sub 45-nm technology nodes. Application of the threshold extraction methods to implement noise analysis is briefly presented to infer the most appropriate extraction method at nanometer technology nodes.展开更多
为实现感应电能传输(Inductive Power Transfer,IPT)系统在变负载条件下的恒流/恒压高效输出,提出一种基于频率切换的LCC-S型IPT系统参数配置及优化方法。从LCC-S补偿拓扑入手,分别得到系统恒流或恒压零相位角(Zero Phase Angle,ZPA)输...为实现感应电能传输(Inductive Power Transfer,IPT)系统在变负载条件下的恒流/恒压高效输出,提出一种基于频率切换的LCC-S型IPT系统参数配置及优化方法。从LCC-S补偿拓扑入手,分别得到系统恒流或恒压零相位角(Zero Phase Angle,ZPA)输出的条件方程,并推导了电流增益、电压增益与系统参数之间的定量关系;进一步通过定义系统的输出增益比,分析了恒流/恒压模式下输出增益、负载电阻与整体效率的关系;在此基础上,通过选取最佳的输出增益值,使得系统整体效率达到了全局最大化。仿真结果表明,负载电阻在3~300Ω的变化范围内包括恒流/恒压模式切换瞬间都能保持稳定的输出,并且恒流/恒压模式下均能实现ZPA运行,同时系统整体效率都维持在90%以上。展开更多
This paper proposes a design and control approach to parallel resonant converter(PRC) based battery chargers.The proposed approach is particularly suitable for the constant-current constant-voltage(CC-CV)charging meth...This paper proposes a design and control approach to parallel resonant converter(PRC) based battery chargers.The proposed approach is particularly suitable for the constant-current constant-voltage(CC-CV)charging method, which is the most commonly utilized one.Since the PRC is operated at two different frequencies for each CC and CV charging modes, this approach eliminates the need for complicated control techniques such as the frequency-control and phase-shift-control.The proposed method not only simplifies the design and implementation processes of the converter unit but also simplifies the design of output filter configuration and decreases the number of the required components for the control of the charger.The proposed method is confirmed by two experimental setups.The results show that the designed charger circuit ensured a very stable constant current in CC charging phase, where the charging current is fixed to 1.75 A.Although a voltage increase in CV phase is observed, the charger circuit is able to decrease the charging current to 0.5 A in CV phase, as depicted in battery data-sheet.The efficiency of the charger is figured out to be in the range of 86%-93% in the first setup, while it is found to be in the range of 78%-88% in the second setup,where a high frequency transformer is employed.展开更多
A 5.0-V 2.0-A flyback power supply controller providing constant-voltage （CV） and constant-current （CC） output regulation without the use of an optical coupler is presented. Dual-close-loop control is proposed her...A 5.0-V 2.0-A flyback power supply controller providing constant-voltage （CV） and constant-current （CC） output regulation without the use of an optical coupler is presented. Dual-close-loop control is proposed here due to its better regulation performance of tolerance over process and temperature compared with open loop control used in common. At the same time, the two modes, CC and CV, could switch to each other automatically and smoothly according to the output voltage level not sacrificing the regulation accuracy at the switching phase, which overcomes the drawback of the digital control scheme depending on a hysteresis comparator to change the mode. On-chip compensation using active capacitor multiplier technique is applied to stabilize the voltage loop, eliminate an additional package pin, and save on the die area. The system consumes as little as 100 mW at no-load condition without degrading the transient response performance by utilizing the adaptive switching frequency control mode. The proposed controller has been implemented in a commercial 0.35μm 40-V BCD process, and the active chip area is 1.5×1.0 mm^2. The total error of the output voltage due to line and load variations is less than 4-1.7%.展开更多
感应耦合能量传输(inductively coupled power transfer,ICPT)系统中补偿网络能够改善系统特性,目前针对谐振补偿网络的输出电流和电压特性没有一种简单易行的分析模型。首先分析了LC电路、??型电路和T型电路实现与负载无关的恒流或恒...感应耦合能量传输(inductively coupled power transfer,ICPT)系统中补偿网络能够改善系统特性,目前针对谐振补偿网络的输出电流和电压特性没有一种简单易行的分析模型。首先分析了LC电路、??型电路和T型电路实现与负载无关的恒流或恒压输出的谐振条件,并针对高阶无源谐振网络提出一种建模方法,通过将谐振网络等效成2阶LC网络和多级3阶???型电路或多级3阶T型电路的串联,研究其恒流或恒压输出的物理机理。ICPT系统中双边LCC谐振腔实质上是一个9阶谐振网络,基于所提建模方法,分析双边LCC谐振腔输出电流和电压特性。此外,提出仅切换一次系统工作频率便可以实现系统先恒流再恒压输出的方法,且恒流和恒压模式下系统工作频率均满足SAEJ2954标准要求,分别能实现谐振腔输入电压、电流之间的零相角和原边逆变器MOSFETs的零电压开通。搭建3.3kW电动汽车感应耦合能量传输系统的Matlab仿真平台和实验样机,验证理论分析的正确性和可行性。恒流和恒压模式下实验样机谐振腔的效率分别为92.1%和89.7%。展开更多
文摘The low voltage substrate current （Ib） has been studied based on generation kinetics and used as a monitor of interface states （Nit） generation for ultra-thin oxide n-MOSFETs under constant voltage stress. It is found that the low voltage Ib is formed by electrons tunnelling through interface states, and the variations of Ib（△Ib） are proportional to variations of Nit （△Nit）. The Nit energy distributions were determined by differentiating Nit（Vg）. The results have been compared with that measured by using gate diode technique.
文摘无线电能传输(wireless power transfer,WPT)系统具有安全、可靠、方便等优点。文章在分析WPT系统锂离子电池内阻及其典型充电方式的基础上,通过对WPT原理和谐振拓扑结构的研究,提出了基于LCC-S补偿式谐振拓扑的WPT系统。在电池等效负载变化的情况下,通过合理的参数设计,LCC-S补偿式谐振拓扑结构可以分别实现与负载无关的恒流模式和恒压模式,无需切换拓扑结构。在理论分析的基础上,设计了系统的参数,并通过MATLAB仿真系统搭建仿真模型,验证了研究中的恒流模式和恒压模式。
基金Projects(20676152, 20876178) supported by the National Natural Science Foundation of China
文摘A new insight into the constant current-constant voltage (CC-CV) charge protocol based on the spherical diffusion model was presented. From the model,the CV-charge process compensates,to a large extent,the capacity loss in the CC process,and the capacity loss increases with increasing the charging rate and decreases with increasing the lithium-ion diffusion coefficient and using a smaller τ value (smaller particle-size and larger diffusion coefficient) and a lower charge rate will be helpful to decreasing the capacity loss. The results show that the CC and the CV charging processes,in some way,are complementary and the capacity loss during the CC charging process due to the large electrochemical polarization can be effectively compensated from the CV charging process.
文摘Threshold voltage (V<sub>TH</sub>) is the most evocative aspect of MOSFET operation. It is the crucial device constraint to model on-off transition characteristics. Precise V<sub>TH</sub> value of the device is extracted and evaluated by several estimation techniques. However, these assessed values of V<sub>TH</sub> diverge from the exact values due to various short channel effects (SCEs) and non-idealities present in the device. Numerous prevalent V<sub>TH</sub> extraction methods are discussed. All the results are verified by extensive 2-D TCAD simulation and confirmed through analytical results at 10-nm technology node. Aim of this research paper is to explore and present a comparative study of largely applied threshold extraction methods for bulk driven nano-MOSFETs especially at 10-nm technology node along with various sub 45-nm technology nodes. Application of the threshold extraction methods to implement noise analysis is briefly presented to infer the most appropriate extraction method at nanometer technology nodes.
文摘为实现感应电能传输(Inductive Power Transfer,IPT)系统在变负载条件下的恒流/恒压高效输出,提出一种基于频率切换的LCC-S型IPT系统参数配置及优化方法。从LCC-S补偿拓扑入手,分别得到系统恒流或恒压零相位角(Zero Phase Angle,ZPA)输出的条件方程,并推导了电流增益、电压增益与系统参数之间的定量关系;进一步通过定义系统的输出增益比,分析了恒流/恒压模式下输出增益、负载电阻与整体效率的关系;在此基础上,通过选取最佳的输出增益值,使得系统整体效率达到了全局最大化。仿真结果表明,负载电阻在3~300Ω的变化范围内包括恒流/恒压模式切换瞬间都能保持稳定的输出,并且恒流/恒压模式下均能实现ZPA运行,同时系统整体效率都维持在90%以上。
文摘This paper proposes a design and control approach to parallel resonant converter(PRC) based battery chargers.The proposed approach is particularly suitable for the constant-current constant-voltage(CC-CV)charging method, which is the most commonly utilized one.Since the PRC is operated at two different frequencies for each CC and CV charging modes, this approach eliminates the need for complicated control techniques such as the frequency-control and phase-shift-control.The proposed method not only simplifies the design and implementation processes of the converter unit but also simplifies the design of output filter configuration and decreases the number of the required components for the control of the charger.The proposed method is confirmed by two experimental setups.The results show that the designed charger circuit ensured a very stable constant current in CC charging phase, where the charging current is fixed to 1.75 A.Although a voltage increase in CV phase is observed, the charger circuit is able to decrease the charging current to 0.5 A in CV phase, as depicted in battery data-sheet.The efficiency of the charger is figured out to be in the range of 86%-93% in the first setup, while it is found to be in the range of 78%-88% in the second setup,where a high frequency transformer is employed.
文摘A 5.0-V 2.0-A flyback power supply controller providing constant-voltage （CV） and constant-current （CC） output regulation without the use of an optical coupler is presented. Dual-close-loop control is proposed here due to its better regulation performance of tolerance over process and temperature compared with open loop control used in common. At the same time, the two modes, CC and CV, could switch to each other automatically and smoothly according to the output voltage level not sacrificing the regulation accuracy at the switching phase, which overcomes the drawback of the digital control scheme depending on a hysteresis comparator to change the mode. On-chip compensation using active capacitor multiplier technique is applied to stabilize the voltage loop, eliminate an additional package pin, and save on the die area. The system consumes as little as 100 mW at no-load condition without degrading the transient response performance by utilizing the adaptive switching frequency control mode. The proposed controller has been implemented in a commercial 0.35μm 40-V BCD process, and the active chip area is 1.5×1.0 mm^2. The total error of the output voltage due to line and load variations is less than 4-1.7%.
文摘感应耦合能量传输(inductively coupled power transfer,ICPT)系统中补偿网络能够改善系统特性,目前针对谐振补偿网络的输出电流和电压特性没有一种简单易行的分析模型。首先分析了LC电路、??型电路和T型电路实现与负载无关的恒流或恒压输出的谐振条件,并针对高阶无源谐振网络提出一种建模方法,通过将谐振网络等效成2阶LC网络和多级3阶???型电路或多级3阶T型电路的串联,研究其恒流或恒压输出的物理机理。ICPT系统中双边LCC谐振腔实质上是一个9阶谐振网络,基于所提建模方法,分析双边LCC谐振腔输出电流和电压特性。此外,提出仅切换一次系统工作频率便可以实现系统先恒流再恒压输出的方法,且恒流和恒压模式下系统工作频率均满足SAEJ2954标准要求,分别能实现谐振腔输入电压、电流之间的零相角和原边逆变器MOSFETs的零电压开通。搭建3.3kW电动汽车感应耦合能量传输系统的Matlab仿真平台和实验样机,验证理论分析的正确性和可行性。恒流和恒压模式下实验样机谐振腔的效率分别为92.1%和89.7%。
