Charles G. Bigler

Molded carrier rings for fine pitch surface mount packages

A molded carrier ring concept intended to reduce the incidence of bent leads and coplanarity rejects while providing increased output-to-mix potential and easy standardization for customers and equipment manufacturers is presented. The methodologies used to design a family of molded carrier rings around various quad-flat-pack and plastic quad-flat-pack package types are described. The algorithms and assumptions used to optimize the ring size and shape are discussed. Test contact design and performance, electrical characteristics, and thermal/mechanical modeling are also discussed.<<ETX>>