Advanced cooling system using miniature heat pipes in mobile PC

This paper describes various cooling solutions using heat pipes for cooling of notebook PCs including: (1) a heat pipe with heat spreader plate; (2) a hybrid system, i.e. a heat pipe with heat sink and fan; and (3) a hinged heat pipe system. For heat input of less than 12 W, the thermal resistances measured between the CPU surface and ambient are: >8/spl deg/C/W for system (1) and 4-6/spl deg/C/W for systems (2) and (3). This means that the hybrid system and the hinged heat pipe systems are the most suitable candidates for cooling of the current CPU, which may require heat dissipation of more than 8 W at ambient of 40/spl deg/C and CPU maximum temperature of 95/spl deg/C. Experimental results of these three systems are included and discussed in this paper.