《PCB表贴封装》.pdf

PCB Land Pattern Design and Surface Mount ® Guidelines for QFN Packages Technical Brief April 23, 2009 TB389.6 Authors: Mark Kwoka and Jim Benson Introduction QFN Package Outline Drawings Intersils Quad Flat No Lead (QFN) package family offering Intersil’s individual product data sheets reference to the is a relatively new packaging concept that is currently appropriate Intersil package outline drawings. These in turn experiencing rapid growth. This package family includes the reference compliance to any applicable industry standard general version, QFN, as well as thinner versions such as outlines. For QFNs, the JEDEC MO-220 outline series TQFN, UTQFN, and XQFN. The family encompasses lead generally applies. The QFN dimensions used in the land pitches of 0.4mm and above. A sub-set of the Quad Flat pattern design can be taken from these drawings. No Lead is the Dual sided type (leads on only 2 of the 4 sides) which includes versions such as the DFN, TDFN, General Design Guidelines UTDFN, and XDFN. Within this document, the term QFN The QFN’s die pad and perimeter I/O pads are fabricated will represent all family options. This family offers a variety of from a planar copper lead-frame substrate. This is benefits including reduced lead inductance, a small sized encapsulated in plastic with the bottom of the die pad and near chip