Mauro G. Dresti wrote:
> Where can I get dimensional specifications for Surface Mount Devices?

Reading your question literally, you can get dimensional specifications 
for the DEVICES from any data book. too easy...
If you were really interested in the dimensions of the footprint & land 
patterns: 

Again, many data books have "suggested" footprints but most of them 
differ slightly across different manufacturers, and you don't want to 
make custom pad geometries for every single part in your library based on 
manufacturer's data sheets.

Instead, you may want to get a copy of IPC-SM-782 which is a good 
introduction to how pad sizes are calculated and contains pad sizes for 
the most common components, along with other useful information about 
surface mount technology in general. 

If you just want an excellent source of data for different devices, I 
would recommend Jim Blankehorn's SMT PLUS footprint library. No theory, 
just dimensions for EVERY type of component. If you can find a component 
that isn't in the book, he will create one and send it to you pronto.
His dimensions differ somewhat from the IPC-SM-782 recommendations, but 
he will explain why if you are interested, his data is based on 
experience with thousands of assemblies, and I just plain'ol trust him. 
408-438-6116

onward through the fog....				Jack