【作者】 张锋；

【导师】 朱冰莲； 蒋和权；

【作者基本信息】 重庆大学 ， 电子与通信工程， 2008， 硕士

【摘要】 对于DC/DC电源模块,随着使用领域的不断扩大其工作环境日趋恶劣,要求IC芯片及功率元件有很高的可靠性,DC/DC电源模块热分析及热设计的研究是提高其可靠性的关键。因此,DC/DC电源模块的热分析及热设计是十分必要的。本论文利用有限元软件(ANSYS 11.0)对DC/DC电源模块进行了热分析,评估了该多芯片组件的热特性及各种封装参数对其热特性的影响,提出了改善多芯片组件散热特性及提高其可靠性的方法。论文还利用ANSYS11.0对大功率多芯片组件进行了热分析,同时,提出了改善大功率多芯片组件散热特性的六种热设计措施。本论文所做的主要工作如下:1、针对不同外界环境及不同封装参数下的DC/DC电源模块,利用有限元热模拟技术分析了它的三维温度场,和影响该DC/DC电源模块热特性的一些重要因素,这些因素包括封装底板底面的温度、粘接层的导热系数、基板材料的导热系数、封装底板的导热系数、芯片的功率密度、拓扑结构及外界环境等。2、针对大功率DC/DC电源模块,利用有限元热模拟技术分析了DC/DC电源模块的温度场,通过循序渐进的方法,采用六种热设计措施进行改进。这六种热设计的措施为改善大功率DC/DC电源模块的散热特性及提高其可靠性提供了参考。这六种热设计措施包括:(1)改进基板材料及粘接材料;(2)采用其他底板材料;(3)改进管壳散热结构;(4)采用导热系数好的填充物;(5)改变芯片的面积(6)优化拓扑结构。并研究了大功率DC/DC电源模块使用中温度控制,这部分应用了有限元的热-流体耦合模拟技术。3、通过对DC/DC电源模块的热分析及热设计,为DC/DC电源模块的工艺设计提供了可靠的热分析、热设计数据。仿真结果表明,所进行的设计满足技术要求,其结果可以用于生产中。更多还原

【Abstract】 The thermal analysis and design of DC/DC modular circuit (DC/DC) are very important and indispensable because these are the key step to raise the reliability of DC/DC, which usually work in the circumstance of high temperature and high moisture. The thesis has made a thorough research of the thermal analysis and design of DC/DC with the help of the finite element software(ANSYS11.0) to evaluate nicely and quickly the thermal performance,which is deeply influenced by packaging parameters,and puts forward the methods to improve the radiating performance and reliability of DC/DC,Moreover,the thesis presents five projects that improve the radiating performance of large-power DC/DC on the basis of analyzing the thermal performance of large-power DC/DC using the software (ANSYS11.0). In general the main work of this thesis follow as:1.According to the DC/DC under the different outer circumstances & packaging parameters,taking good advantages of finite element thermal simulation technique,I have analyzed the 3-D temperature field of the DC/DC and the main influencing factors of thermal performance of DC/DC in this article,which involve the temperature on the ground boar of packaging,the conductivity factors of cementation layer,the material of base plate and the ground plate for packaging,topology of electrical circuit,schemethe power density of chip and the outer circumstances.2. According to high power DC/DC,taking advantage of the finite element thermal simulation technique,6 thermal design measures are taken to make better step by step. These 6 measures,which have provided good references for improving the reliability and radiating performance of large-power DC/DC,include:(1)the improving of placode material and splice material;(2) the improving of baseboard material;(3) the improving of structure of baseboard radiator;(4)the using of diathermancy filling;(5) the improving of chip area;(6)optimization topology of electrical circuit.At the same time Study temperature control of using high power DC/DC adopt the finite element simulation technique of thermal-fluid coupling.3. By way of thermal analysis and design of DC/DC,reliable analyzing & designing data have been provided for the DC/DC design. The practice shows that the design satisfied the technical demand and the result can be put into multi-produce.更多还原