Issue link: https://iconnect007.uberflip.com/i/1210212
12 DESIGN007 MAGAZINE I FEBRUARY 2020 tive side. You mentioned that you weren't see- ing many EMI problems due to different ways of doing busses and other tricks that helped re- lieve those issues. Lee Ritchey: I believe that might have been happening because they have big distributed networks in cars, and if you don't do it right, you turn the whole car into an antenna. To An- dy's point, I used to do six to 12 EMI problems a year, but I did only one last year. The source of most EMI is a ripple in the power supply, which is caused by trying to drive these wide data busses for DDR, VME, etc., and the power supply hasn't been designed correctly. When we replace a parallel bus with a differential pair, several things happen all at once. The in- cidence of wide busses switching from zero to Feature Interview by the I-Connect007 Editorial Team The I-Connect007 team met with design ex- pert Lee Ritchey to pick his brain on EMI (Elec- tromagnetic Interference) problems and what can be done to minimize them. Lee explains the issues are almost always tied to power de- livery, as well as the abundant amount of mis- information surrounding this topic. Barry Matties: Thank you for speaking with us, Lee. Andy Shaughnessy: We want to discuss fin- er pitches and features and EMI and EMC be- cause we have talked to people having EMI is- sues, particularly in Germany on the automo- Avoiding EMI Problems With Lee Ritchey