Thermal analysis of power amplifier package in cellular phones

Portable electronic devices, like the cellular phones, offer increasing electronic functions. Radio frequency (RF) components featured by small form factor, high power dissipation and low cost are readily used in such portable products. On the other hand, the RF component packages such as power amplifiers (PA) trend to multi chip package (MCP) and plastic package with organic substrate. The thermal management becomes the challenge related to the component performance and reliability. This paper studies the thermal management of PA MCP under pulsed power excitation. We offer the experimental validated numerical models solved by computational fluid dynamic (CFD) software-FLOTHERM to predict maximum junction temperature of PA. Thermal analyses of different substrate materials, substrate structures and the effects of thermal vias are discussed. The results show that after proper thermal design, the maximum junction temperature can satisfy the PA package thermal requirement.