A Design Approach for the Systematic Improvement of Support Locations for Vibrating Circuit Cards

Abstract

This paper approaches the problem of improving an initial guess at support locations for a vibrating circuit card so as to increase the first natural frequency of the card. The finite element method and structural dynamic modification techniques are combined with a simple sequential search algorithm to systematically improve the location of point supports for a circuit card populated with components. It is found that the proposed methodology can be useful for determining the support locations of a circuit card so as to increase its fundamental natural frequency. A case study is presented in which the original support locations on an existing commercial power supply circuit card are systematically improved giving a better than two fold increase in the natural frequency. Additionally, finite element modeling approaches for determining the modal characteristics of a circuit card are compared with experimental results.