非均匀芯片布局的LED模组散热性能研究

Thermal Performance of Uneven Chip Arrangements for High-power LED Module

芯片阵列均匀排列的常规大功率LED模组因温度场叠加会导致中心温度过高、温度分布不均匀。在理论分析面热源温度分布函数及多热源相互影响的基础上提出了一种LED芯片外密内疏排列的模组设计方案,并与ANSYS有限元仿真的结果进行了对比验证。当芯片按照优化后的对数和幂函数分布时芯片最高温度比常规均匀排列时均低约5℃,芯片温度的方差降低约56%。外密内疏的非均匀芯片排列方案在基板较小、较薄时对散热效果的改善更好。

Because of the linear superposition of temperature field,the temperature distribution of normal evenly placed chips in high-power LED module is usually unevenly presented with high core temperature.In this paper,based on theoretically analyzing the function of temperature distribution of plane heat source and the interaction of multi-heat sources,a principle of being dense inside and sparse outside to arrange the chip arrays was proposed.Optimized logarithmic and power arrangements are respectively concluded by Matlab and compared by ANSYS simulation.It is indicated that the highest temperature of the chip arranged in accordance with the optimized arrangement principles is about 5 ℃ lower than that of the evenly arranged chips;the variance is 56%lower than that of the evenly arranged chips.The heat dissipation improvement of unevenly arranged chip arrays is greater for the modules with narrower and thinner substrate.