Doug Smith

Many system design problems result from electrical resonances in the physical structures of the system, such as PCB construction and mounting, heat sink construction and mounting, chassis construction, unintended resonances of system antennas, and system cables both internal and external. If these problems are thought of in terms of resonances (LC and transmission lines), the problems are often more easily found and solved. Techniques for finding, characterizing, determining if a specific resonance is a problem or is harmless, and fixing those resonances that are causing problems are presented. The presentation is practical (as opposed to theoretical). Results are presented from various types of systems.

Outlin:

1. How to measure resonances

2. Examples of measurements and implications

3. Methods to kill the Q of resonances

4. Effect of system resonances on emissions and radiated immunity

5. Effect of system resonances on ESD performance

6. Testing resonances to see if they are a problem

7. Equipment recommendations

8. Summary

Biography:

Doug Smith received a B.E.E.E. degree from Vanderbilt University in 1969 and an M.S.E.E. degree from the California Institute of Technology in 1970. In 1970, he joined AT&T Bell Laboratories as a Member of Technical Staff. He retired in 1996 as a Distinguished Member of Technical Staff. From February 1996 to April 2000 he was Manager of EMC Development and Test at Auspex Systems in Santa Clara, CA. Mr. Smith currently is an independent consultant specializing in high frequency measurements, circuit/system design and verification, switching power supply noise and specifications, EMC, and immunity to transient noise. He is a Senior Member of the IEEE and a former member of the IEEE EMC Society Board of Directors.

His technical interests include high frequency effects in electronic circuits, including topics such as Electromagnetic Compatibility (EMC), Electrostatic Discharge (ESD), Electrical Fast Transients (EFT), and other forms of pulsed electromagnetic interference. He also has been involved with FCC Part 68 testing and design, telephone system analog and digital design, IC design, and computer simulation of circuits. He has been granted over 15 patents, several on measurement apparatus.

He is author of the book High Frequency Measurements and Noise in Electronic Circuits. His very popular website, http://emcesd.com (www.dsmith.org), draws many thousands of visitors each month to see over 250 technical articles as well as other features.