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Date: | Fri, 3 May 1996 16:12:13 -0500 (CDT) |
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Randy,
The solder coating thickness is located in Table 3-5 (page 13). For
Class 2, the requirement is 2.5 micrometers (0.0001") minimum.
IPC-D-275 superseded IPC-D-949 upon its publication in September 1991.
This is specified on the cover of IPC-D-275 (at least, it is on the cover
of the copy I have).
IPC-D-275 does not list a solder coating thickness. Rather, it states
that the requirement shall meet the solderability requirements of IPC-S-804
(which was superseded by J-STD-003). Neither S-804 nor J-003
stipulates a minimum thickness. Rather, they contain test
methods (edge dip, solder float, wetting balance, etc.) by which one can
determine solderability (as opposed to measuring thickness; what a concept).
Therefore, if you meet the requirements of D-275, you might meet the
requirement (2.5 um) of IPC-D-949.
If a minimum thickness must be specified, I would use IPC-RB-276,
amendment 1.
Mike Buetow
IPC Technical Staff
2215 Sanders Road
Northbrook, IL 60062
P: 847-509-9700, ext. 335
F: 847-509-9798
[log in to unmask]
On Thu, 2 May 1996 [log in to unmask] wrote:
> I have a customer specification requirement to inspect solder coating
> thickness per IPC-D-949 Class 2. I reviewed the Design Guide and did not
> find any solder coat thickness requirements.
>
> Where in this IPC spec is the solder coat thickness requirements?
>
> What is the relationship of IPC-D-949 and IPC-D-275?
>
> If I use the solder coat thickness in IPC-D-275, do I meet the
> requirements of IPC-D-949?
>
> Your help is appreciated.
>
> Randy Reed
> Merix Corporation
> [log in to unmask]
>
>
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