典型封装芯片的热阻网络模型研究-精密仪器及机械专业论文.docxVIP

万方数据 万方数据 摘 要 准确预测芯片的工作温度可以提高电子设备的可靠性。电子设备热设计时， 需要建立简化并且准确的芯片热模型，从而节约计算资源，缩短设计周期。 本文首先根据几种典型封装芯片的工艺和参数，建立了塑料焊球阵列(PBGA)、 倒装焊球阵列(FCBGA)、四边引脚扁平封装(QFP)三种封装形式的含芯片内部结构 特性的详细模型。通过与实际芯片的结—环境的热阻值误差的对比，验证了详细 模型。 然后，根据芯片各自的结—壳热阻和结—板热阻，建立了相应的双热阻模型。 接着，利用详细模型在多组边界条件下的仿真结果，建立了各芯片的热阻网络模 型，并得出了其相对误差。 最后，对全部模型进行了板级热仿真。利用详细模型对双热阻模型、热阻网 络模型进行了验证。通过芯片上表面中心、下表面中心及侧面中心监测点的温度 值对比，得到不同模型在不同功耗、不同风速条件下的误差变化。 本文深入分析了双热阻模型的局限性，建立了三种典型封装芯片的详细模型， 验证了热阻网络模型的实用性，得出了热阻网络模型的误差变化规律，为电子设 备热设计中芯片的热建模和板级热分析提供了依据。 关键词：芯片 典型封装 热阻网络模型 电子设备热设计 万方数据 万方数据 Abstract It is necessary to have a good forecast of thermal characteristics of chips in order to improve the electronic equipment reliability. A simplified but accurate thermal model of chip should be established when conducting electronic equipment thermal design, saving resources and reducing designing time. Firstly, several detail chip models with internal structure characteristics are established based on typical chip packaging processes and parameters, and the packages are PBGA, FCBGA and QFP respectively. Detail models are verified through comparing the errors of junction-ambient thermal resistance. Then, dual thermal resistances models are established based on the junction-case thermal resistance and junction-board thermal resistance of each chip. After that, the models of thermal resistances network of each chip are established based on the simulation results of the detail models with several boundary condition sets, obtaining the relative errors. Finally, board-level simulations are carried out for all models. Dual thermal resistances models and thermal resistances network models are verified with the help of detail models. Comparing the temperatures at the center of the top surface of the chip, at the center of the bottom surface of the chip and at the center of the side surface of the chip, error variations of models with different powers and different windy conditions are obtained. In this paper, the limitations of the dual thermal resistances