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A Novel Integrated Circuit Driver for LED Lighting  [PDF]
Yanfeng Jiang, Dong Zhang, Ming Yu
Circuits and Systems (CS) , 2014, DOI: 10.4236/cs.2014.57018
Abstract: A novel integrated circuit for driving LED lighting has been proposed, designed and fabricated. Besides the typical parts of LED driver, an integral part was added at the output terminal of error amplifier in the driver. In this way, a novel average current mode can be set up to take the place ordinary peak current control mode. In addition, a BUCK low-level topology was adopted, too. It can be used to drive up to eight 1 W HB LED lights with 350 mA constant current. In this way, the LED driver displays high performance, in which output current with less 1% error and total efficiency as high as 96%. The feasibility of the design has been verified by actual measurement on the fabricated chip.
Research of an Efficient LED Lighting Driver Based on Boost-Buck Converter  [PDF]
Renbo Xu, Yongzhi Li, Lixin Zhong, Jiaming Liu
Circuits and Systems (CS) , 2014, DOI: 10.4236/cs.2014.56017
Abstract:

Boost-Buck converter is widely used in LED lighting drivers. In this paper, Boost-Buck main circuit related characteristics are firstly discussed, and then a new Boost-Buck high power efficient double loop control strategy is built by adopting error amplifier and integrator control method. It is demonstrated that the new system has many advantages such as high efficiency, fast response, strong anti-interference, good stability after analyses and simulations of its working dynamic characteristics.

A Single Stage High Power Factor Supply Based on Integrated Buck Flyback Converter
ELIZABETH PAUL,PROF. ALEYAS M.V,PROF. ANNIE P.OOMMEN
International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering , 2013,
Abstract: In recent years, power converters are used to get high power factor. This paper presents an integrated converter topology for driving HB LEDs which provides high power factor. The integrated buck flyback converter is a single stage, low cost, high power factor AC-DC converter with fast output regulation. The converter is used to provide power factor correction in streetlight application. To obtain high power factor, the buck stage and flyback stage are operated in discontinuous mode. Dimming operation of HB LED is also described. A closed loop is used for enabling the PWM dimming. The simulation studies using MATLAB/Simulink is also presented. Hardware setup of open loop is described.
Design and research of an LED driving circuit with accurate proportional current sampling mode
精密比例采样模式LED驱动电路设计和研究

Guo Wei,Yang Xing,Zhu Dazhong,
郭维
,杨幸,朱大中

半导体学报 , 2010,
Abstract: 基于CSMC 0.5μm标准CMOS工艺设计研制了一种精密比例采样模式的LED驱动电路,电路通过运算放大器反馈控制使采样MOS管和功率MOS管的三端电位相等,实现采样电流对输出电流的精确传感,达到更好的恒流特性。通过电路的小信号模型分析,得到精密比例采样模式的小信号等效输出电阻远大于传统比例采样模式,同时保证了系统的稳定性。经电路仿真及流片测试,表明当LED驱动电流为350mA,电源电压6V并正负波动10%时,改进的精密比例采样模式LED驱动电路比传统比例采样模式LED驱动电路的恒流特性稳定度提高了41%。
Design, Analysis and Implementation of a new topology of multi phase synchronous buck converter under current mode control
Nittala S K Sastry,Dr. Swapnajit Pattnaik
International Journal of Electronics and Computer Science Engineering , 2012,
Abstract: This paper presents a new PWM Multi phase DC-DC converter under current mode control with an auxiliary circuit which provides zero voltage switching in order to meet the power supply requirements of the processors of modern electronic equipments like laptops, mobiles, and PDAs etc which require more than 70 A current, lower voltage and better transient response.The multi phase topology benefits in high current, good efficiency and better current transient response. High current multi phase buck converters found applications in advanced data control, solid state lasers, communication equipment and Pentium processors etc. In this paper designed of three phase DC-DC converter 100W, 12V/1V under current mode control is discussed in detail and the simulation results are presented to support the theoretical analysis.
功率LED替代灯的新颖谐振式Buck镇流器  [PDF]
曲小慧,SiuChungWong,ChiKongTse,张建忠
电工技术学报 , 2012,
Abstract: LED灯发光效率高,寿命长,因此具有巨大的应用前景,并有望取代白炽灯。LED灯是低压电流型器件,需要LED镇流器(驱动电路)将公共电网的高压交流电转换为适合LED的低压直流电。为了保证整个LED照明系统具有高效率和长寿命,LED镇流器必须具有以上特性。相比于采用变压器降压,无变压器的降压变换器可以达到更高的效率,但此类变换器,如Buck变换器,在低占空比时要承受长时间的二极管续流,导通损耗大,效率低。因此,本文提出一种新颖的谐振式Buck镇流器,利用谐振可实现高电压转换比,转换效率高,工作时间长,且可以与已有的白炽灯调光器配合工作,可直接安装在白炽灯具上。实验结果证明了该镇流器的有效性,且成本低,适合于目前LED替代灯场合。
有源纹波补偿BUCK型LED驱动电源  [PDF]
唐治德,王官涛,杨红,张正茂,陶凛
重庆大学学报 , 2012, DOI: 10.11835/j.issn.1000-582X.2012.12.008
Abstract: 驱动电源是发光二极管(light-emittingdiode,LED)照明的重要组成部分。针对因电解电容自身特性导致的驱动电源寿命与LED的长寿命不匹配这一问题,提出了一种有源纹波补偿降压(BUCK)型拓扑结构。该拓扑充分结合了开关电源和线性电源的特点,用辅助有源电路补偿电感纹波电流来取代传统电解电容滤波。文中详细分析了该拓扑的结构组成及工作原理,并且通过仿真和实验验证了该拓扑的结构有效性。理论分析和实验结果均表明,采用有源纹波补偿的拓扑结构可将电感纹波电流完全补偿,使得电路输出为直流。
Design of a High Frequency Driving Circuit of Surface Acoustic Wave Transducer
Guan Zhao
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104737
Abstract:
In this paper, a high frequency driving circuit of surface acoustic wave transducer has been designed to separate oil from oil/water mixed droplet. The transmission frequency of the surface acoustic wave transducer driving circuit can be up to 1 MHz. The transmit frequency of conventional ultrasonic driving circuit is mostly 40 kHz. However, the high transmit frequency driving circuit presents a good stability and accuracy. By establishing the surface acoustic wave driving circuit model, the actual circuit and debugging verification, the driving circuit can excite the frequency signal required for the experiment. Thus, the surface acoustic wave driving circuit could provide necessary technical support for application in other fields.
BUCK变换器中过零检测电路的设计
Design of zero-crossing detection circuit in BUCK converter
 [PDF]

庞屹林,夏晓娟,范阳,吉新村,张洪俞
- , 2017,
Abstract: 针对同步BUCK变换器轻载下会发生电流倒灌从而降低芯片效率这一问题,设计了一款基于CSMC 0.35 μm CMOS工艺的低功耗过零检测电路。该电路不使用运算放大器实现了电流比较的功能,同时增加抗振铃电路,得到稳定的电感电流。此过零检测电路已成功应用于一款基于COT控制模式的BUCK变换器芯片,经流片测试,电感电流在9 mA时同步整流管关断,且电路静态功耗仅为1 μA。
The synchronous BUCK converter under light load will occur on the current irrigation.To solve this problem for reducing the chip efficiency,a low power zero crossing detection circuit is fabricated by using CSMC 0.35 μm CMOS process.The circuit does not use the operational amplifier to achieve the current comparison function,while increasing the anti ringing circuit,thus a stable inductor current can be obtained.The zero crossing detection circuit has been successfully applied to a BUCK converter chip based on COT control mode.When the inductor current is 9 mA,the synchronous rectifier is turned off and the static power consumption of the circuit is only 1 μA
LED汽车前照灯有源纹波补偿Buck型恒流驱动电源  [PDF]
唐治德,赵丹,黄小程,张晓斌
北京理工大学学报 , 2014,
Abstract: 针对一般照明LED驱动电源中输出滤波电解电容的寿命与LED的长寿命极不匹配的问题.提出了一种有源纹波补偿的Buck型LED驱动电路.电路中用有源纹波补偿支路替代输出滤波电解电容,抵消电感纹波电流,使LED灯组获得恒定直流,达到LED的理想驱动状态.为了减小纹波补偿支路的损耗,必须控制电感电流的峰值和谷值,滞环电流控制可有效地满足这个要求.设计和制作了输出功率为30W的滞环电流控制、有源纹波补偿BUCK型LED驱动电源.仿真和实验验证了上述新型电源的可行性.
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