Thermal performance limits of the QFP family

Abstract

The quad flat package (QFP) finds wide use in current electronic systems, PCs, and workstations, housing a variety of devices. This study projects the thermal performance limits of the QFP family. The metrics chosen are the maximum power dissipated for constraints of junction temperature (<105/spl deg/C) and board temperature (<90/spl deg/C), under natural and forced air convection (/spl sim/1 m/s) equipment operating conditions. Simulation studies using a finite difference based thermal software for IC packages investigated the relative roles of package and equipment parameters toward the thermal performance. Experimental data from the 132 PQFP (plastic QFP) were used to validate the methodology. The limits are presented from a chip designer's as well as the package/equipment engineer's perspective. Further, the studies allow for the prediction of thermal performance of PQFPs that incorporate enhancements. The study covers plastic (132, 160, 208, and 304 PQFPs) as well as ceramic versions (132, 196, and 256 CQFPs) of the QFP family.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>