Articles from May 1997 Issue

A simple method to estimate heat sink air flow bypass

May 1st, 1997

Introduction After selecting or designing a heat sink based upon a given air velocity orvolumetric flow rate through the fins, the thermal designer needs to determinethe total amount of flow which must be delivered in…read more

Calculating interface resistance

May 1st, 1997

Figure 1. Ceramic Package – Aluminum Heat SinkAssembly Introduction The exposed surface area of many of today’s high powered electronic packagesis no longer sufficient for the removal of the heat generated during normaloperation. Heat sinks…read more

Forced convection cooling of airborne electronics

May 1st, 1997

Figure 1. AFT description Fin pitch = 25.01 per in = 985 per mPlate spacing, b = 0.200 in = 5.08 x 10-3 m Fin Length = 0.111 in = 2.8 x 10-3 m Flow…read more

Packaging: designing for thermal performance

May 1st, 1997

Figure 1. Various leadframe and BGA packages Introduction The well-established trend within the electronics industry to provide everincreasing computing power at less cost seems to defy the laws of economics.However, this industry has not been…read more

Thermal Conductivity

May 1st, 1997

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…read more

Thermal resistance: an oxymoron?

May 1st, 1997

Introduction Dark light, deafening silence, cruel kindness, living dead, fuzzy logic,honest politics. The adjectives seem to contradict the substantives; such afigure of speech is called an oxymoron. It will be argued within this articlethat ‘thermal…read more