在电子电路及仪器的设计与制作中经常要用到一些功耗较大的元器件,如大功率三极管、功率集成电路等。这些元器件由于在正常工作时消耗较大的功率,导致温度升高,如不采取适当的散热措施,轻则达不到元器件本身的额定技术指标,重则造成元器件损坏。 1.电子元件的最大功率消耗与极限工作温度电子元器件的最大消耗功率是与元器件的极限工作温度、工作环境温度以及散热器(热阻)密切相关的,其关系可用公式P_(CM)=(Tj—Ta)/R_T来表示,式中P_(CM)——元器件的最大功耗,Tj——最高工作温度(一般锗材料为75～100℃,硅材料为150～200℃),Ta——工作环境温度,R_T——总热阻。由此可见, In the design and production of electronic circuits and equipment often use some of the more expensive components, such as high-power transistors, power integrated circuits. As these components consume more power during normal operation, resulting in temperature rise, if not take appropriate cooling measures, ranging from less than the rated component of the technical indicators, resulting in damage to components. 1. The maximum power consumption of electronic components and the maximum operating temperature The maximum power consumption of electronic components and components is the maximum operating temperature, operating temperature and heat sink (thermal resistance) are closely related, the relationship can be used formula P_ (CM) = (Tj-Ta) / R_T, where P_ (CM) is the maximum power consumption of the component, Tj is the maximum operating temperature (typically 75 to 100 ° C for germanium material and 150 to 200 ° C for silicon material) , Ta-- working environment temperature, R_T-- total thermal resistance. Thus,