The most cogent discussion of secondary side pads for wave soldering is in
"Manufacturing Techniques For Surface Mounted Assemblies" R. J. Klein
Wassink & M. M. F. Verguld, Electrochemical Publications, 1995, ISBN
0901150304.

We align most SMT devices with the direction of travel as we would align a
similarly leaded PTH component.  The exception is devices with leads on four
sides, such as QFP and PLCC, which are aligned 45° to the wave.

Other points:
* QFP, PLCC, and SOP variants have thief [scavanger] pads trailing the last
pads to see the wave.
* Generally, wave side SMT pads are narrower and have less protrusion from
the component body than primary side pads.

Dave Fish

----- Original Message -----
From: "Patrick Lam" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, October 23, 2001 8:26 AM
Subject: [TN] Land pattern for wave soldering


> Hi Technetters,
>
> Is there a need to have different SMD land size/ pattern for wave
soldering? Any
> suggestion is appreciated.
>
> Thanks,
> Patrick
>
> --------------------------------------------------------------------------
-------
> Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
> To unsubscribe, send a message to [log in to unmask] with following text in
> the BODY (NOT the subject field): SIGNOFF Technet
> To temporarily halt delivery of Technet send the following message: SET
Technet NOMAIL
> Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail Archives
> Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
additional
> information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
ext.5315
> --------------------------------------------------------------------------
-------
>

---------------------------------------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------