基于嵌入式处理器的vlsi芯片的温度自动控制英文翻译 毕业设计 .doc

Embedded Processor Based Automatic Temperature Control of VLSI Chips Abstract This paper presents embedded processor based automatic temperature control of VLSI chips, using temperature sensor LM35 and ARM processor LPC2378. Due to the very high packing density, VLSI chips get heated very soon and if not cooled properly, the performance is very much affected. In the present work, the sensor which is kept very near proximity to the IC will sense the temperature and the speed of the fan arranged near to the IC is controlled based on the PWM signal generated by the ARM processor. A buzzer is also provided with the hardware, to indicate either the failure of the fan or overheating of the IC. The entire process is achieved by developing a suitable embedded C program. Keywords: Temperature sensor, ARM processor, VLSI chips, Brushless DC motor 1.Introduction With the phenomenal developments in VLSI technology, the ambitious IC designers are trying to put more transistors in to smaller packages. So, the ICs run at higher speeds and produce large amount of heat which creates the problem of thermal management. For example, nowadays the CPU chips are becoming smaller and smaller with almost no room for the heat to escape. The total power dissipation levels now reside on the order of 100 W with a peak power density of 400-500 W/Cm2, and are still steadily climbing. As the chip temperature increases its performance is very much degraded by parameters shift, decrease in operating frequencies and out-of specification of timings. So the high speed chips must be cooled to maintain good performance for the longest possible operating time and over the widest possible range of environmental conditions. The maximum allowable temperature for a high speed chip to meet its parametric specifications depends on the process and how the chip is designed. Among the various cooling techniques, heat sinks, heat pipes, fans and clock throttling are usually employed. Among these t