System thermal analysis for mobile phone

Thermal management is an important issue for mobile phone due to its small space and high power consuming density. On the basis of system experiment and numerical simulation, a thermal resistance network is established to analyze the whole mobile phone system in this paper. Our analysis shows that the maximum permission of power consumption is limited by the small surface area of mobile phone; and the surface temperature must be considered except the temperature of chips. Emphasis for thermal enhancement should be put on balance of cooling paths, for example, add material with high thermal conductivity between chip and battery, and make best use of the periphery surface area. Transient cooling method like phase change material can be considered also. In addition, this paper introduces some skills about how to calculate spreading thermal resistance for anisotropic and laminated heat sink.