Testing

Like it or not, most electronic designs today are subject to formal EMI testing. So even if you are new to EMI/EMC (electromagnetic interference/compatibility), you need to understand what is involved and how to best prepare for a trip to the EMI test lab.

Reading EMI test results from a test lab is very much like a radiologist reading a CT scan or MRI results. To the novice, it may seem very hard to decipher what is what, but to the trained eye, the test results provide a road map to not only the frequencies of the outages, but also an indication of what or where the outages more than likely are emanating from.

This article shows how electromagnetic simulation tools can be used to investigate effects of high-speed signals in cable harnesses in a vehicle: cross talk, radiation and interference with a receiving antenna. Results are presented for two types of digital sequences and compared with standards. Cable shielding is designed to be adequate without adding unnecessary weight.