Thermal Conductivity： What is it and Why You Should Care

　　導(dǎo)熱系數(shù)：材料傳熱能力的量度。給定兩個(gè)表面的一個(gè)材料的兩側(cè)與它們之間的溫度差，熱導(dǎo)率是傳熱單位時(shí)間和單位面積，除以溫度差1的熱能轉(zhuǎn)移。

　　導(dǎo)熱系數(shù)是描述材料傳熱能力的體積特性。在圖1中的公式中，導(dǎo)熱系數(shù)是比例因子K。傳熱的距離被定義為通過材料傳遞的熱速率（Q），從溫度T1到溫度T2，當(dāng)T1 T2 T2 2。

　　Thermal conductivity of materials plays a significant role in the cooling of electronics equipment; from the die where the heat is generated to the cabinet where the electronics are housed， conduction heat transfer and， subsequently， thermal conductivity， are the integral components of the overall thermal management process.

　　The path of heat from the die to the outside environment is a complicated process that must be understood when designing a thermal solution. In the past， many devices were able to operate without requiring an external cooling device like a heatsink. In these devices， the conduction resistance from the die to the board needed to be optimized， as the primary heat transfer path was into the PCB. As power levels increased， heat transfer solely into the board became inadequate. Much of the heat is now dissipated directly into the environment through the top surface of the component. In these new higher-powered devices， low junction-to-case resistance is important， as is the design of the attached heatsink.