Telephone equipment has traditionally been housed in large buildings, sheds and outdoor cabinets. The cooling of these facilities has been carried out using traditional methods. However, in many of the new systems being developed and deployed such as broadband ISDN, cellular and/or cable, heat dissipation densities will increase substantially [1]. Furthermore, the introduction … [Read more...]
Coefficient of thermal expansion
As complexity increases and dies and packages become even larger, temperature gradients also increase, leading to problems with thermal mismatch. Hence, thermomechanical analysis grows in importance. Apart from the temperature differences, the most important parameter describing thermally induced stress is the coefficient of thermal expansion (CTE, or °), expressed in units of … [Read more...]
Highly emissive ion beam textured surfaces for improved cooling of electronic devices
Continuous improvements in the cooling of electronic systems will berequired to keep pace with the rapid development of higher power chips.Currently, effective cooling relies (in part) on high surface area heatexchangers. Further improvements could be realized by increasing thesurface area of these devices. However, increasing the size of heatexchanger components is not a … [Read more...]
Thermal Conductivity
For most calculations regarding the thermal analysis of electronic systems, thermal conductivities of solid materials are required. It is felt that many designers would welcome a comprehensive list showing these values for certain classes of objects, such as PCB materials, leadframes, molding compounds, alloys etc.. This issue starts with 45 leadframe materials, the data for … [Read more...]
Measuring chip temperatures with thermochromic liquid crystals
Introduction Measurement of the temperature distribution of an operating electroniccomponent, including its junction and case temperatures, is necessary tocompletely characterize the thermal and electrical performance of today's highpower density electronic components. As part of the characterization process,thermal designers must be able to predict and verify the … [Read more...]