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© Freescale Semiconductor, Inc., 2011-2014. All rights reserved.
Freescale Semiconductor
Application Note
AN4388
Rev. 2.0, 2/2014
1 Introduction
This document provides guidelines for handling and assembly
of Freescale QFP packages during Printed Circuit Board
(PCB) assembly.
Guidelines for PCB design, rework, and package performance
information such as Moisture Sensitivity Level (MSL) rating,
board level reliability, mechanical and thermal resistance data
are included for reference.
2 Scope
This document contains generic information that
encompasses various Freescale QFP packages assembled
internally or at external subcontractors. It should be noted that
the specific information about each device is not provided.
This document serves only as a guideline to help users
develop a specific solution. Actual experience and
development efforts are still required to optimize the assembly
process and application design per individual device
requirements, industry standards such as IPC and JEDEC,
and prevalent practices in user’s assembly environment.
For assistance for more details or questions about the specific
devices contained in this note, visit www.freescale.com or
contact the appropriate product application team.
Quad Flat Package (QFP)
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
2 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
3 Quad Flat Package (QFP) . . . . . . . . . . . . . . . . . . . . . . .2
4 Printed Circuit Board Guidelines . . . . . . . . . . . . . . . . . .4
5 Board Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
6 Repair and Rework Procedure . . . . . . . . . . . . . . . . . . .13
7 Board Level Reliability . . . . . . . . . . . . . . . . . . . . . . . . .17
8 Thermal Characteristics . . . . . . . . . . . . . . . . . . . . . . . .18
9 Case Outline Drawing, MCDS and MSL Rating. . . . . .21
10 Package Handling . . . . . . . . . . . . . . . . . . . . . . . . . . .25
11 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
12 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
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