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Freescale Semiconductor, Inc.
Application Note
© Freescale Semiconductor, Imnc., 2013 - 2014. All rights reserved.
Document Number: AN1902
Rev. 7.0, 9/2014
Contents
1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
3 DFN and QFN Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
4 Printed Circuit Board Guidelines . . . . . . . . . . . . . . . . . . . . . 8
5 Board Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6 Repair and Rework Procedure . . . . . . . . . . . . . . . . . . . . . . 19
7 Board Level Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
8 Thermal Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
9 Case Outline Drawing, MCDS and MSL Rating . . . . . . . . 26
10 Package Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
11 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
12 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
1 Introduction
This application note provides guidelines for the handling and
assembly of Freescale QFN and DFN packages during printed
circuit board (PCB) assembly, and guidelines for PCB design and
rework, and package performance information (such as Moisture
Sensitivity Level rating, board level reliability, mechanical and
thermal resistance data).
2 Scope
Contains generic information for various Freescale QFN and DFN
packages assembled internally (or at external subcontractors).
Specific information about each device is not provided. To develop
a specific solution, actual experience and development efforts are
required to optimize the assembly process and application design
per individual device requirements, industry standards (such as
IPC and JEDEC), and prevalent practices in the assembly
environment. For more details about the specific devices contained
in this note, visit
www.freescale.com or contact the appropriate
product application team.
Assembly Guidelines for QFN (Quad Flat No-lead) and
DFN (Dual Flat No-lead) Packages
