been there, seen that, almost fixed it.....
In a small controller I found the CMOS ASIC to be responsible for outages
during Radiated emissions testing. Using ENSCAN, I found that all the
interface leads carried minute(?) levels of noise that when I hooked up
wiring radiated like crazy. Terminating the lines made little difference, but
I had great success putting RC filters close to where a lead left the PCB.
Anyone interested in a paper on this topic?
Best regards,
Derek N. Walton
Owner L F Research EMC Design and Test Facility