We have some problems with the footprints for the SOT23 wave soldering.

 

We have calculated this footprint with the calculator.

 

Now we have the problem of poor wetting.

 

The wave soldering diection is correct.

 

My question is also is there difference between reflow soldering footprint and the wave soldering footprint?

 

With kind regards,

André

mailto:akridree@onsbrabantnet.nl" rel="nofollow - akridree@onsbrabantnet.nl

 

The standard says that the same footprint pattern can be used for reflow, infrared, vapor phase, full wave and selective wave solder processes.

 

We've been using the same math for the past 10 years for land pattern calculations and thousands of users developing millions of library parts and no one has ever commented on solder joint or bridging problems.

 

So this leads me to conclude that since you're alone in this wave solder problem, that you look at the assembly shop and their wave solder process. I would also like to hear from the assembly shop what their recommended footprint would be for the same component. i.e.: is their recommendation different than IPC-7351?

 

Also, the user can change all the program rules and we don't know what rules you changed to create your library and you did not mention what IPC 3-tier environment you used. All this information is important to us. Poor Wetting can be caused by contamination of the solder or improper solder temperature or conveyor belt moving too fast.