IPC-CM-770D-1996.pdf - 第17页

IPC-CM-770

Januaty

1996

which uninterrupted service is desired but is not critical.

Certain cosmetic imperfections are allowed.

CLASS 3 High Reliability Electronic Products

Includes the equipment for commercial and military prod-

ucts where continued performance or performance on

demand is critical. Equipment downtime cannot be toler-

ated, and functionality is required for such applications as

life support items, or missile systems. Printed boards and

printed board assemblies in this class are suitable for appli-

cations where high levels of assurance are required and

service is essential.

The land patterns in this standard have the capability of

accommodating all three performance classifications.

1.4 ASSEMBLY TYPES

A type designation signifies fur-

ther sophistication describing whether components are

mounted on one or both sides of the packaging and inter-

connecting structure. Type

1

defines an assembly that has

components mounted on only one side; type

2

is an assem-

bly with components on both sides. Type

2

is limited to

only class B or C assemblies.

Figure

1-1

shows the relationship of two types of assem-

blies.

The need to apply certain design concepts should depend

on the complexity and precision required to produce a par-

ticular land pattern or printed board structure. Any design

class may be applied to any of the end-product equipment

categories; therefore, a moderate complexity (Type 1B)

would define components mounted on one side (all surface

mounted) and when used in a Class

2

product (dedicated

service electronics) is referred to as type lB, Class

2.

The

product described as Type lB, Class

2

might be used in any

of the end-use applications; the selection of class being

dependent on the requirements of the customers using the

application.

1.5 Presentation

All dimensions and tolerances are

expressed in metric. Reference information is shown in

parentheses

(

).

2.0 REFERENCE DOCUMENTS

The following documents, of the issue currently in effect

form a part of this document to the extent specified herein.

Other documents listed are for reference purposes to assist

the user.

2.1 Institute for Interconnecting and Packaging Elec-

tronic Circuits (IPC)’

IPC-T-50

Terms and Definitions

IPC-SCIO

Post Solder Solvent Cleaning Handbook

IPC-AC-62

Post Solder Aqueous Cleaning Handbook

IPC-RF-245

Performance Specification for Rigid-Flex

Printed Boards

IPC-D-249

Design Standard for Flexible Single- and

Double-Sided Printed Boards

IPC-FC-250

Performance Specification for Single- and

Double-Sided Flexible Printed Wiring

IPC-D-275

Design Standard for Rigid Printed Boards and

Rigid Printed Board Assemblies

IPC-RB-276

Qualification and Performance Specification

for Rigid Printed Boards

IPC-D-322

Guidelines for Selecting Printed Wiring Board

Sizes Using Standard Panel Sizes

IPC-MC-324

Qualification and Performance Specification

for Metal Core Boards

IPC-D-325

Documentation Requirements for Printed

Boards, Assemblies, and Support Drawings

IPC-D-330

Design Guide

IPC-PD-335

Electronic Packaging Handbook

IPC-C-406

Design and Application Guidelines for Surface

Mount Connectors

IPC-A-600

Acceptability of Printed Boards

IPC-A-61

O

Acceptability of Electronic Assemblies

IPC-R-700

Suggested Guidelines for Modification,

Rework, and Repair of Printed Wiring Boards and Assem-

blies

IPC-SM-782

Surface Mount Design and Land Pattern

Standard

IPC-SM-784

Guidelines for Chip-On-Board Technology

Implementation

IPC-AJ-820

Assembly and Joining Handbook

IPC-CA-821

General Requirements for Thermally Con-

ductive Adhesives

IPC-CC-830

Electrical Insulating Compounds for Printed

Board Assemblies

IPC-SM-840

Qualification and Performance of Permanent

Polymer Coating (Solder Mask) for Printed Boards

IPC-H-855

Hybrid Microcircuit Design Guide

SMC-TR-001

An Introduction to Tape Automated Bonding

Find Pitch Technology

l.

Institute for Interconnecting and Packaging Electronic Circuits,

2215

Sanders Road, Northbrook,

IL

60062.

1-2

COPYRIGHT Association Connecting Electronics Industries

Licensed by Information Handling Services

COPYRIGHT Association Connecting Electronics Industries

Licensed by Information Handling Services

January

1996

IPC-CM-770

m

Components (mounted) on only one side of the board

Through-hole

Simple

I

uu

iz

o0

e

CHIP COMPONENT SOE

'OLDER

m

COMPONENT

PLCC CHIP

PASTE DIP DIP

..

SMTITH

. . . . .

. .

..

,,

"

"".

m&A&2

b

:

Complex

i:

II

li

i¡

,

I,

II

u uu u

PLCC

CHID

BGA

&

Similar, Not Shown

m

Components (mounted) on both sides of the board

?-Sided Thru-hole (NOT RECOMMENDED)

SMT

Complex

FPT

Simple

THISMT

1:

i

'4

II

-CHIPe COMPONENT

Wire bond

or

tab IC chip

attachment

PLCC

CHIP

m

COMPONENT

THT

0

m

DIP

COB

Q

I

TAB

Flip Chip

UFTP

..

"".

..

"".

..

II

..

D

'"'2

"

I

U U

uuu

u u

CHIP

1

/

FLIP

W

"

..

-

FPT PKG.

U

SOlC

!CHI/

COMPONENT

&

Similar, Not Shown

(selectively attached)

Class A

=

Through-hole component mounting only

Class B

=

Surface mounted components only

Class C

=

Simplistic through-hole and surface mounting intermixed assembly

Class

X

=

Complex intermixed assembly, through-hole, surface mount, fine pitch and BGA

Class

Y

=

Complex intermixed assembly, through-hole, surface mount, ultra fine pitch, chip scale

Class

2

=

Complex intermixed assembly, through-hole, ultra fine pitch, COB, flip chip, TAB

IPC-1-001229

Figure 1-1 Electronic Assembly Types

2.2 Joint Industry Standards' J-STD-003

Solderability Tests for Printed Boards

J-STD-001

Requirements for Soldered Electrical and Elec-

J-STD-004

Requirements for Electronic Soldering Fluxes

tronic Assemblies

J-STD-005

Requirements and Test Methods for Solder

J-STD-002

Solderability Tests for Component Leads, Ter-

minations, Lugs, Terminals and Wires

J-STD-006

General Requirements and Test Methods for

Paste

1-3

COPYRIGHT Association Connecting Electronics Industries

Licensed by Information Handling Services

COPYRIGHT Association Connecting Electronics Industries

Licensed by Information Handling Services

IPC-CM-770

Januaty

1996

Electronic Grade, Soft Solder Alloys and Fluxed and Non-

Fluxed Solid Solders for Electronic Soldering Applications

2.3 Department of Defense2

MIL-STD-1

O0

Engineering Drawing Practices

MIL-STD-129

Marking for Shipment and Storage

MIL-STD-202

Test Methods for Electronic and Electrical

Component Parts

MIL-STD-454

Standard General Requirements for Elec-

tronic Equipment

MIL-STD-883

Test Methods and Procedures for Microelec-

tronics

MIL-STD-1344

Test Methods for Electrical Connectors

MIL-1-7444

Insulation Sleeving, Electrical, Flexible

MIL-C-11268

Parts, Materials, and Processes, Used in

Electronic Equipment

MIL-P-13949

Plastic Sheet, Laminated, Metal Clad, for

Printed Wiring Boards

MIL-S-1 9500

Semiconductor Devices, General Specifica-

tion

MIL-1-23053

Insulation Sleeving, Electrical, Heat Shrink-

able

MIL-P-28809

Printed Wiring Assemblies

MIL-M-3851

O

Semiconductor Devices, General Specifica-

tion

MIL-P-55110

Printed Wiring Boards

MIL-S-83502

Sockets, Plug-In Electronic Component,

Round Style

2.4 Electronic Industries Association3

JEDEC-95

JEDEC Registered and Standard Outlines for

Solid State Products

RS-167

Type Designation for Receiver Type Tube Sockets

RS-186-9E

Standard Test Methods for Passive Electronic

Component Parts-Method

9,

Solderability Rev. E

RS-192

Holder Outlines and Pin Connections for Quartz

Crystal Units

RS-198

Ceramic Dielectric Capacitors

RS-228

Fixed Electrolytic Tantalum Capacitors

RS-296

Lead Taping, Axial Components

RS-367

Dimensional and Electrical Characteristics Defin-

ing Receiver Type Sockets

RS-376

Fixed Film Dielectric Capacitors in Metallic and

Non-Metallic Cases for D.C. Application

RS-415

Dimensional and Electrical Characteristic Defin-

ing Dual-In-Line-Type Sockets

RS-428

Type Designation System for Microelectronic

Devices

RS-468

Lead Taping, Radial Components

RS-471

Symbol and Label for Electrostatic Sensitive

Devices

RS-481

Lead Taping, Leadless Components

RS-488

Sockets, Individual Lead Types (for Electrical and

Electronic Components)

2.5 American National Standards Institute4

ANSI Y-1 4.5

Dimensioning and Tolerancing

2.6 Underwriters Laboratories5

UL-1244

Electrical and Electronic Measuring and Testing

Equipment

2.7 American Society for Testing and Materials6

B25

Standard Nominal Diameters and Cross-Sectional

Areas of AWG Sizes of Solid Round Wires Used as Elec-

trical Conductors

F72

Gold Wire for Semiconductor Lead Bonding

F487

Fine Aluminum-

1

%

Silicon Wire for Semiconductor

Lead Bonding

D3295

Standard for PTFE Tubing

2.8 Other Documents

IEC-348

Safety Requirements for Electronic Measuring

Apparatus

FCC

Docket

20780

3.0 TERMS AND DEFINITIONS

Terms and definitions used herein are in accordance with

IPC-T-50 except as otherwise specified. Note: Any defini-

tion denoted with as asterisk

(*)

is a reprint of the defini-

tion defined in IPC-T-50.

2. Publications are available from Naval Publications and Form Center, 5801 Tabor Road, Philadelphia, PA 19120.

3. Electronic Industries Association, 2001

"I"

Street, NW, Washington, DC 20006.

4. American National Standards Institute, 11 W. 42nd St., New York, NY 10036.

5. Underwriters Laboratories, Inc., 333 Pfingsten Rd., Northbrook, IL 60062.

6. American Society for Testing and Materials, 1916 Race St., Philadelphia, PA 19103-1187.

1-4

COPYRIGHT Association Connecting Electronics Industries

Licensed by Information Handling Services

COPYRIGHT Association Connecting Electronics Industries

Licensed by Information Handling Services