Component Placement for Reliability on Conductively Cooled Printed Wiring Boards

Abstract

With the increased demand for highly reliable electronic equipment and limitations that make improvements to the reliability of individual components difficult to obtain, methods to improve the reliability at higher levels of packaging are being sought. This article presents the mathematical theory for improving reliability by appropriately locating components on conductively cooled printed wiring boards based on the thermal behavior of the components on the board. Placement techniques are then constructed to minimize the total failure rate of the collection of components.