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Circuit Board Rework and Repair Guide

7.1.3 Solder Joint Acceptance Criteria

Printed Board Type: R/F/W/C
Skill Level: Intermediate
Conformance Level: N/A
Revision: E
Revision Date: Mar 15, 2004

OUTLINE
This document includes figures and tables for solder joint acceptability criteria on a variety of component types.

NOTE
Information in these tables has been drawn a variety of industry sources. For more information on solder joint acceptability criteria refer to:
IPC-A-610    Acceptability of Electronic Assemblies
J-STD-001    Requirements for Soldered Electrical and Electronic Assemblies

ACCEPTABILITY REFERENCES
IPC-A-610 5.0 Component Installation
IPC-A-610 6.0 Soldering
IPC-A-610 12.0 Surface Mount Assemblies
 
PROCEDURE REFERENCE
1.0 Foreword
7.1.1 Soldering Basics
7.1.2 Preparation For Soldering And Component Removal


Figure 1: Dimensional Criteria for Through Hole Components

 

Table 1: Acceptable Solder Criteria for Through Hole Components
Feature Dim Class 1 Class 2 Class 3
Circular wetting of solder of the lead and plated hole barrel on the component side. 1 Not Specified 180° 270°
Plated hole fill. 2 Not Specified 75% 75%
Circular fillet and wetting of solder of the lead and plated hole barrel on the solder side. 1 270° 270° 330°
Percent of the land area covered with solder on component side. 3 0 0 0
Percent of the land area covered with solder on the solder. 4 75% 75% 75%



Figure 2: Dimensional Criteria for Chip Components


Table 2: Acceptable Solder Criteria for Chip Components

Feature Dim Class 1 Class 2 Class 3
Maximum Component Side Overhang 1 Less than 50% of the component termination width or 50% of the pad width whichever is less. Less than 50% of the component termination width or 50% of the pad width whichever is less. Less than 25% of the component termination width or 25% of the pad width whichever is less.
Maximum Component End Overhang 2 Not permitted. Not permitted. Not permitted.
Minimum End Joint Width 3 50% of the component termination width or 50% of the pad width whichever is less. 50% of the component termination width or 50% of the pad width whichever is less. 75% of the component termination width or 75% of the pad width whichever is less.
Minimum Side Joint Length 4 Evidence of proper wetting. Evidence of proper wetting. Evidence of proper wetting.
Maximum Fillet Height 5 Solder may overhang the pad but must touch the non-soldered portion of the component package body. Solder may overhang the pad but must touch the non-soldered portion of the component package body. Solder may overhang the pad but must touch the non-soldered portion of the component package body.
Minimum Fillet Height 6 Evidence of proper wetting. Evidence of proper wetting. Equal to the solder thickness plus 25%, or equal to the solder thickness plus 0.50 mm (.020"), whichever is less.
Minimum Solder Thickness 7 Evidence of proper wetting. Evidence of proper wetting. Evidence of proper wetting.
Minimum End Overlap 8 Evidence of any overlap is required. Evidence of any overlap is required. Evidence of any overlap is required.



Figure 3: Dimensional Criteria for J Lead Components

Table 3: Acceptable Solder Criteria for J Lead Components

Feature Dim Class 1 Class 2 Class 3
Maximum Lead Side Overhang 1 No more than 50% of the lead width. No more than 50% of the lead width. No more than 25% of the lead width.
Maximum Lead Toe Overhang 2 Not specified. Not specified. Not specified.
Minimum Lead End Joint Width 3 50% of the lead width. 50% of the lead width. 75% of the lead width.
Minimum Side Joint Length 4 Evidence of proper wetting. Side joint length must exceed 150% of the lead width. Side joint length must exceed 150% of the lead width.
Maximum Fillet Height 5 No maximum, but solder must not touch the component package body. No maximum, but solder must not touch the component package body. No maximum, but solder must not touch the component package body.
Mininimum Heel Fillet Height 6 Evidence of proper wetting. Equal to the solder thickness plus 50% of lead thickness. Equal to the solder thickness plus 100% of lead thickness.
Mininimum Solder Thickness 7 Evidence of proper wetting. Evidence of proper wetting. Evidence of proper wetting.


Figure 4: Dimensional Criteria for Gull Wing Components

Table 4: Acceptable Solder Criteria for Gull Wing Components


Feature Dim Class 1 Class 2 Class 3
Maximum Lead
Side Overhang		 1 No more than 50% of the lead width or 0.50 mm (.020") whichever is less. No more than 50% of the lead width or 0.50 mm (.020") whichever is less. No more than 25% of the lead width or 0.50 mm (.020") whichever is less.
Maximum Toe
End Overhang		 2 Toe overhang is acceptable as long as it does not violate electrical clearance. Toe overhang is acceptable as long as it does not violate electrical clearance. Toe overhang is acceptable as long as it does not violate electrical clearance.
Minimum End Joint Width 3 50% of the lead width. 50% of the lead width. 75% of the lead width.
Minimum Side Joint Length 4 Equal to the lead width or 0.50 mm (.020") whichever is less. Equal to the lead width or 0.50 mm (.020") whichever is less. Equal to the lead width or 0.50 mm (.020") whichever is less.
Maximum Heel Fillet Height 5 No maximum, but solder must not touch the component package body. No maximum, but solder must not touch the component package body. No maximum, but solder must not touch the component package body.
Minimum Heel Fillet Height 6 Evidence of proper wetting. Equal to the solder thickness plus 50% of lead thickness. Equal to the solder thickness plus 100% of lead thickness.
Minimum Heel Fillet Thickness 7 Evidence of proper wetting. Evidence of proper wetting. Evidence of proper wetting.


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