Surface flatness is an important issue for thermal designers as it is directly related to thermal contact resistance between surfaces. In this column, the definitions of surface flatness related parameters are discussed. These definitions are presented here as in the ASME B46.1-1995 standard [1]. Surfaces are characterized by three main parameters: roughness, waviness, and … [Read more...]
The Temperature Ratings Of Electronic Parts
Introduction Semiconductor parts are most often specified for use in the "commercial" 0 to 70°C and, to a lesser extent, in the "industrial" -40 to 85°C operating temperature range. These operating temperature ratings generally satisfy the demands of the dominant semiconductor customers in the computer, telecommunications, and consumer electronic industries. There is also a … [Read more...]
Thermal Interface Materials: A Brief Review of Design Characteristics and Materials
Introduction In the past few decades, as microprocessors have continued to evolve along Moore's law, providing increased functionality and performance, there has been an associated increase in cooling demand driven both by the increase in raw power and in local power densities on the die, commonly referred to as "hot spots"[1, 2]. Considerable attention has therefore been given … [Read more...]
Prediction of Thermal Contact Resistance
All engineering surfaces exhibit some level of microscopic roughness. The resistance to heat flow through a contact interface occurs because only a small portion (usually 1-2%) [1] of the nominal surface area is actually in contact. Heat may pass through the interface via three paths: conduction through the contact spots, conduction through the gas present in the gap between … [Read more...]
Problems with Thermal Interface Material Measurements: Suggestions for Improvement
Preface Increasingly it is apparent that measuring the thermal properties of Thermal Interface Materials (TIMs) causes much irritation for vendors and users alike. This article focuses on various measurement and standardization aspects and offers a strategy to overcome the problems. It is essentially an abbreviated version of a paper presented at SEMITHERM '03 … [Read more...]
- « Previous Page
- 1
- …
- 71
- 72
- 73
- 74
- 75
- …
- 85
- Next Page »
