Displacement Theory for Fixturing Design of Thin Flexible Circuit Board Assembly

Abstract

The compliant nature of flexible substrates subject to assembly forces can result in severe misregistration of the component leads and substrate bond pads, leading to assembly process defects. Specially dedicated tooling for fixturing thin flexible substrates in standard surface mount assembly equipment is gaining importance. This paper focuses on developing a theoretical foundation for implementing Smart Tooling of fixturing thin flexible substrates. The primary goals are to determine the impact of fixturing tooling on assembly process quality, to develop a displacement theory to predict transverse displacements, and to analyze the optimum perimeter fixturing configuration. The predictive capabilities of the transverse displacement model are verified.