Studies show that Li-Zn ferrites can successfully suppress EMI. N.C. Joshi and S.S. Islam, Ph.D. Jamia Islamia University, Jamia Nagar, India Anjali Verma, Ph.D. Indian Institute of Technology, New Delhi, India Recent technological development has been characterized by an unprecedented proliferation of digital technology in information and communications equipment. The … [Read more...]
Interference Suppression Using a Balanced MLCC
An innovative capacitor design can provide more RFI suppression in a substantially smaller package. Steve Weir and James Muccioli X2Y Attenuators, LLC, Erie, PA, USA Instrumentation amplifiers are often employed in hostile noise environments. Sensor lead cables may pick up substantial RF radiation, particularly if they are long and/or not well shielded. When applied to the … [Read more...]
Building a State-of-the-Art 5-Meter Chamber
An efficient shield room for automotive testing progresses from design to finished structure. Michael Koffink and Bob Mitchell Intertek Four years ago, we noticed a growing demand for EMC testing from the automotive industry. As cars and trucks now feature myriad on-board electronic devices, they are increasingly susceptible to stray emissions while simultaneously functioning … [Read more...]
2007 Update on Intentional Electromagnetic Interference (IEMI) and High-altitude Electromagnetic Pulse (HEMP)
Of concern are high-level electromagnetic fields that will create serious problems for electronic systems on the Earth’s surface, including critical infrastructure. Dr. William A. Radasky, Ph.D., P.E. Metatech Corporation, Goleta, CA INTRODUCTION Over the past seven years, a substantial number of articles have been written by this author and others identifying the threat … [Read more...]
Achieving More Accurate Measurement of Conducted RF Emissions Using Modified AMNs
Measurement uncertainty for common-mode disturbances can be reduced from about 22 dB to a maximum of a few dB. Mart Coenen Philips Applied Technologies, Eindhoven, the Netherlands INTRODUCTION In early 1980, extensive discussions were held within the IEC CISPR/A working group regarding the definition of the impedance characteristics and the RF emission limits attained via … [Read more...]
Power Quality Effects on the Reliability and Susceptibility of EMI Filters
EMI filter performance plays a critical role in limiting emissions and also impacts the immunity of end-use equipment to electrical disturbances. Philip F. Keebler and Kermit O. Phipps EPRI, Knoxville, Tenn., USA Today, electronic equipment is commonplace in every residential, commercial, and industrial environment. Moreover, this equipment depends on increasingly complex … [Read more...]
Reverberation Chamber for EMC Testing
The reverberation chamber provides the most realistic simulation/equivalency for electronics functioning within a cavity. Er-Ping Li and Xing-Chang Wei Electromagnetic Labs, Institute of High Performance Computing, Singapore INTRODUCTION The problem is familiar, but growing. The widespread and ever-growing use of electronic devices with high-speed components increases the … [Read more...]
Understanding Inductance in the Real-World
As soon as current flows through metal conductors, inductance exists. Bruce Archambeault, Ph.D. IBM Distinguished Engineer, IBM, Research Triangle Park, NC, USA The concept of inductance is one of the most misunderstood concepts in electrical engineering. Terms such as ‘self inductance’, ‘loop inductance’, ‘partial inductance’, ‘mutual inductance’ are used with little … [Read more...]
Antenna Fundamentals
A proper understanding of antennas requires familiarity with electromagnetics, circuit theory, electronics and signal processing. Candace Suriano, Ph.D., Suriano Solutions John Suriano, Ph.D., Nidec Motors, Auburn Hills, MI, USA Tom Holmes, Agilent Technologies, Tipp City, OH, USA Qin Yu, Alcatel-Lucent, Columbus, OH, USA How does an antenna pick up a signal and convert it to … [Read more...]
Magnetic Shielding Basics
Growing complexity in electronics heightens the need for magnetic shielding. Richard Vance Ad-Vance Magnetics, Inc., Rochester, IN, USA Without magnetic shielding, much of today’s sophisticated electronic gear would be larger, less efficient, and in some magnetic environments, completely non-functional. Today’s complex components are extremely sensitive, and miniaturization … [Read more...]
