IPC-SM-782A 表面安装设计和焊盘设计标准(带BGA).pdf - 第146页

Page Intentionally Left Blank IPC-SM-782 Subject Components with Gullwing Leads on Four Sides Date 8/93 Section 11.0 Revision P a g e2o f2 电子技术应用ｗｗｗ．ＣｈｉｎａＡＥＴ．ｃｏｍ

1.0 INTRODUCTION

This section covers land patterns for components with gull-

wing leads on four sides. Each subsection contains informa-

tion in accordance with the following format:

1.0 Scope

2.0 Applicable Documents

3.0 General Component Description (Figure 1)

4.0 Component Dimensions (Figure 2)

5.0 Land Pattern Dimensions (Figure 3)

6.0 Tolerance and Solder Joint Analysis (Figure 4)

The following is the table of contents for this section:

2.0 APPLICABLE DOCUMENTS

The following documents, of the issue in effect on the revision

date of this section, form a part of this specification to the

extent specified herein.

2.1 Electronic Industries Association (EIA)

EIA-481-A

Taping of Surface Mount Components for Auto-

matic Placement

EIA-481-3

32 mm, 44 mm, and 56 mm Embossed Carrier

Taping of Surface Mount Components for Automated Han-

dling

JEDEC Publication 95

Registered and Standard Outlines for

Solid State and Related Products:

MO 108, issue ‘‘A,’’ dated 10/90

MO 112, issue ‘‘A,’’ dated 8/90

MO 136, issue ‘‘A,’’ dated 8/92, now MS-026

MO 143, issue ‘‘A,’’ dated 3/93, now MS-029

2.2 Electronic Industries Association of Japan (EIAJ)

EIAJ-ED-7404

General Rules for the Preparation of Outline

Drawings of Integrated Circuits

2.3 International Electrotechnical Commission (IEC)

IEC 97

Grid Elements

3.0 General Information

3.1 General Component Description

The four-sided gull

wing family is characterized by gull wing leads on four sides of

a square or rectangular package. The family includes both

molded plastic and ceramic case styles. The acronyms PQFP,

Plastic Quad Flat Pack and CQFP, Ceramic Quad Flat Pack,

are also used to describe the family.

There are several lead pitches within the family from 1.0 mm

to 0.30 mm. High lead-count packages are available in this

family that accommodate complex, high lead-count chips.

3.2 Marking

The PFQP and CQFP families of parts are

generally marked with manufacturers part numbers, manufac-

turers name or symbol, and a pin 1 indicator. Some parts may

have a pin 1 feature in the case shape instead of pin 1 mark-

ing. Additional markings may include date code/

manufacturing lot and/or manufacturing location.

3.3 Carrier Package Format

Components may be pro-

vided in tube but packaging tray carriers are preferred for best

handling and high volume applications. Bulk packaging is not

acceptable because of lead coplanarity required for place-

ment and soldering.

3.3 Process Considerations

PQFP and CQFP packages

are normally processed by solder reflow operations.

High lead-count fine pitch parts may require special process-

ing outside the normal pick/place and reflow manufacturing

operations.

Separate pick/place, excise, and reflow processes are some-

times used as an alternate to normal SMT processes.

1. Application for copies should be addressed to Global Engi-

neering Documents, 1990 M St. N.W., Washington, DC

20036.

2. Application for copies should be addressed to IEC, 3 rue

de Varembe, PO Box 131 - 1211 Geneva 20, Switzerland

IPC-SM-782

Surface Mount Design

and Land Pattern Standard

Date

8/93

Section

11.0

Revision Subject

Components with

Gullwing Leads on Four

Sides

Page1of2

电子技术应用　　　　　ｗｗｗ．ＣｈｉｎａＡＥＴ．ｃｏｍ

Page Intentionally Left Blank

IPC-SM-782

Subject

Components with Gullwing Leads on Four Sides

Date

8/93

Section

11.0

Revision

Page2of2

电子技术应用　　　　　ｗｗｗ．ＣｈｉｎａＡＥＴ．ｃｏｍ

1.0 SCOPE

This subsection provides the component and land pattern

dimensions for PQFP (Plastic Quad Flat Pack) components.

Basic construction of the PQFP device is also covered. At the

end of this subsection is a listing of the tolerances and target

solder joint dimensions used to arrive at the land pattern

dimensions.

2.0 APPLICABLE DOCUMENTS

See Section 11.0 and the following for documents applicable

to the subsections.

Electronic Industries Association (EIA)

JEDEC Publication 95

Registered and Standard Outlines for

Solid State and Related Products, ‘‘Low Profile Plastic Quad

Flat Pack Family 0.025 Lead Spacing (Gullwing), Outline

MO-086, issue ‘‘B,’’ dated 6/90

Application for copies should be addressed to:

Global Engineering Documents

1990 M Street N.W.

Washington, DC

3.0 COMPONENT DESCRIPTIONS

Flatpacks are widely used in a variety of applications for com-

mercial, industrial, or military electronics.

3.1 Basic Construction

See Figure 1. PQFPs have leads

on a 0.635 mm pitch.

3.1.1 Termination Materials

Leads must be solder-

coated with a tin/lead alloy. The solder should contain

between 58 to 68% tin. Solder may be applied to the leads by

hot dipping or by plating from solution. Plated solder termina-

tions should be subjected to post-plating reflow operation to

fuse the solder. The tin/lead finish should be at least 0.0075

mm [0.0003 in] thick.

3.1.2 Marking

All parts shall be marked with a part number

and an index area. The index area shall identify the location of

pin 1.

3.1.3 Carrier Package Format

The carrier package for-

mat for PFQPs is the tube format; however, packaging trays

provide the best handling capability.

3.1.4 Process Considerations

PQFPs are usually pro-

cessed using standard solder reflow processes. Parts should

be capable of withstanding ten cycles through a standard

reflow system operating at 215°C. Each cycle shall consist of

60 seconds exposure at 215°C.

IPC-782-11-1-1

Figure 1 PQFP construction

IPC-SM-782

Surface Mount Design

and Land Pattern Standard

Date

5/96

Section

11.1

Revision

Subject

PQFP

Page1of4

电子技术应用　　　　　ｗｗｗ．ＣｈｉｎａＡＥＴ．ｃｏｍ