> I am looking for the specs for trace width, spacing, and length.
and
> What I need to know is the clearance between pads.
Isn't trace/pad spacing at least partly a function of the voltage are
expected to carry? And, I understand, that as you approach RF
frequencies, the rules change--or at adherence becomes much more
meaningful to correct outcomes (e.g., see this from TI:
http://focus.ti.com/lit/an/szza009/szza009.pdf ).
Have you looked at the manufacturability layout hints provided by PCB
manufacturing facilities, e.g., this from ExpressPCB:
http://www.expresspcb.com/ExpressPCBHtm/Tips.htm , or this from a
consultant:
http://www.pdcamerica.com/guidelines.htm ?
There are standards for PCB design, too; a page such as
http://www.smps.us/pcb-design.html will give you a set of terms to feed
to Google.
Or punt with Wikipedia:
http://en.wikipedia.org/wiki/Printed_circuit_board .
All that should give you enough numbers to take any number of sides to
the discussion.
HTH,
Daniel