TOP-10 DC/DC

自2005年开始,《今日电子》杂志开始评选TOP-10DC／DC奖。每年,评审组专家从当年的候选产品中,根据“在技术或应用方面取得显著进步,具有开创性的设计,性价比显著提高”三个方面对产品分别打分,最后选出获奖产品。     

2009 TOP-10 DC/DC 获奖产品

专家评审组成员方佩敏教授北京航空航天大学陈永真教授辽宁工业大学邢岩教授南京航空航天大学降压型DC/DC转换器ADP2108这款600mA     

Current-source parallel-resonant DC/DC converter

This paper introduces, analyzes, and experimentally verifies a novel DC/DC converter called the current-source parallel-resonant converter. The converter consists of a large choke inductor, two switches, and a parallel-resonant circuit. Each switch consists of a MOSFET in series with a diode. It has a nonpulsating input current with a very low AC ripple. The MOSFETs are driven with respect to ground and, therefore, have a simple gate-drive circuit. The analysis of the converter is carried out in the frequency domain using Fourier series techniques. Analytical expressions are derived for performance parameters of the converter. A prototype of the converter circuit was designed, built, and tested. The theoretical results were in good agreement with the experimental results     

DC

近期．单反市场最受期待的产品非尼康D40x莫属了，D40x的上市弥补了尼康在低价位千万像素级别无产品的空白，形成了其完整的产品线，D200、D80，D40x和D40．随着D70s的停产，D40x充当这一价位的角色，直接挑战佳能400D及索尼a100．目前千万像素已经普及到了低档单反之中，不难看出尼康D40x是2007年单反市场中的一颗重磅炸弹，相信随着D40x的上市单反的价格战又会再次拉开。     

DC

本月市场动态：第十届中国国际照相机械影像器材与技术博览会（2007 CHINA P＆E）于7月1日在北京落幕，作为目前中国规模最大的摄影器材展会，其影响力不言而喻。国际知名的几大品牌，如佳能．尼康，索尼均带来了主流的产品，腾龙、适马也推出了各自最新的镜头。从展出的产品来看．有一个非常明显的信号就是，     

如何使DC/DC转换器无需散热器

本文重点分析标准的半砖2.3”×2.4”DC/DC转换器。一般来说,同类型最好的肖特基二极管转换器能够提供150瓦或30安的输出。但由于使用温度环境变坏,转换器实际能够输出的功率通常要低于这个数字。     

升压型DC—DC转换器MAC1676及其在后备电源的中的应用

升压型DC－DC转换器MAX1676是MAXIM公司生产的新型直流转换器。高转换效率、低静态电流、超小型封装、输出电压可调的特点使其成仪器仪表后备电源较为理想的选择器件。文中介绍MAX1676的基本结构、典型应用,并结合实际介绍了该器件在扩展后备电源中的特殊应用。     

DC

本月市场动态： 今年初期随着佳能5D以及尼康D200价格的多次杀低，预示着今年数码单反市场必写是不平静的。     

DC

一般来说数码相机镜头等效焦距在200mm以上的机型，就可以称之为长焦相机。长焦数码相机因其超长的焦距、丰富的功能受到了消费者的喜爱，它们也一直是消费级数码相机市场的热点所在。但是由于过大的体积，让携带长焦相机成为一件很费力的事情。现在，随着机身设计的进一步轻便和防抖技术的进一步成熟，长焦相机正在逐渐变得更加小巧、实用。原来拥有超长焦距的机型现在也可以像卡片机一样随身携带，近期上市的索尼DSC—H3就是其中不错的一款。     

数码相机电源DC/DC逆变电路研究

根据逆变系统的构成原理。设计出一种适合数码相机电源部分的DC／DC电路，并详细分析了所设计电路的工作原理和特性。     

Pseudo-resonant full bridge DC/DC converter

A DC-DC power converter topology that combines the ease of control and wide range of conventional DC-DC converters, with low switching losses, low dv/dt and low electromagnetic interference that is typical of zero voltage switched resonant converters is proposed. Consequently, the ratings of these components are substantially lower than for similarly rated resonant topologies. While resonant elements are used to ensure zero voltage switching of all devices, they have little or no role in the actual power transfer and can thus be reasonably sized. As the resonant elements are not involved in the primary power transfer, the converter is referred to as a pseudo-resonant converter. It is shown that the converter offers significantly higher levels of performance than either the pulse width-modulated (PWM) or typical resonant converters. Operation at very high frequencies is possible and is shown with the fabrication of a 200 W 1 MHz DC-DC converter     

超小型直流电源电压变换电路

介绍了一种新颖的超小型DC／DC电压变换电路，对电路的工作原理进行了理论分析，并用仿真算法对理论计算结果进行了校验，最后给出了基于Maxim器件的实用稳压电路。     

Multifrequency averaging of DC/DC converters

This paper presents some of the issues involved in applying frequency-selective averaging to modeling the dynamic behavior of pulsewidth-modulated (PWM) DC-DC converters. We use the boost converter as an example to show the details involved in deriving some novel extended averaged models, and we use simulations to highlight the accuracy of the models even when traditional small-ripple conditions are not satisfied     

小型化直流电源发展动态

随着电子整机向小型化、轻量化方向的发展，对整机所用的直流稳压电源也提出了小型化的要求。本文叙述了国外ＤＣ／ＤＣ变换器的研究与开发情况，介绍了国内发展集成化直流稳压电源的现状，分析了国内市场对ＤＣ／ＤＣ变换器的需求。对国内外在该领域的技术水平进行了比较，提出了发展我国小型化直流电源的对策。     

DC-DC转换器架构提升并联操作

为了提升功率水平或提供冗余备份，设计师都会并联多个供电器或DC/DC转换器。无论他们选用的是哪一种并联模式，均流是十分重要的考虑因素。因为备有均流的架构，可以减轻热处理要求，改善瞬态反应，同时可以延长同一数组内的模块寿命。目前两种最常采用的并联方法是驱动器/倍增器（主/从）数组及DC耦合单线并联，但两者各有缺点，设计师需要一种可以兼备传统并联方法的优点，同时避免它的缺点的方法。有一种由具有智能的模块组成的数组，利用单线AC连接模块，在同一时间内只有一个模块发出指令，可以满足他们的需要，只需要用极简单的…     

开关电容DC—DC变换器的设计方法

在对开关电容ＤＣ－ＤＣ变换器进行稳态分析的基础上,研究了面向设计的几个关键技术问题,提出了开关电容ＤＣ－ＤＣ变换器的设计方法,并通过了实验和仿真的手段加以验证。     

Asymmetrical pulse-width-modulated resonant DC/DC convertertopologies

This paper presents asymmetrical pulse-width-modulated (APWM) DC/DC resonant converter topologies that exhibit near-zero switching losses while operating at constant and very high frequencies. The converters include a bridged chopper to convert the DC input voltage to a high-frequency unidirectional AC voltage, which in turn is fed to a high-frequency transformer through a resonant circuit. The bridged chopper has two switches that alternately conduct. The duty cycles of the conduction of the switches are complementary with one another and are varied to control the output voltage. Three resonant circuit configurations suitable for this type of control are presented. Frequency domain analysis of the converter is given, and performance characteristics are presented. Experimental results for a 48-5 V, 30 W converter show an efficiency of 88% at a constant operating frequency of 1 MHz     

DC/DC模块电源发展动态

本文综述了当前DC/DC模块电源的发展动态,介绍中间总线结构IBA、DC/DC模块电源标准以及它们对DC/DC模块电源产品发展的影响.     

Zero-voltage DC/DC converter with asymmetric pulse-width modulation for DC micro-grid system

This paper presents a zero-voltage switching DC/DC converter for DC micro-grid system applications. The proposed circuit includes three half-bridge circuit cells connected in primary-series and secondary-parallel in order to lessen the voltage rating of power switches and current rating of rectifier diodes. Thus, low voltage stress of power MOSFETs can be adopted for high-voltage input applications with high switching frequency operation. In order to achieve low switching losses and high circuit efficiency, asymmetric pulse-width modulation is used to turn on power switches at zero voltage. Flying capacitors are used between each circuit cell to automatically balance input split voltages. Therefore, the voltage stress of each power switch is limited at V_in/3. Finally, a prototype is constructed and experiments are provided to demonstrate the circuit performance.