An Effective Approach to Mitigate IC Radiated Susceptibility in EM Far-Field Region

An effective approach to mitigate the radiated susceptibility of integrated circuits (ICs) to electromagnetic (EM) disturbances in far-field zone is described. It relies on dielectric loading which confines the reactive fields inside the dielectric load to improve the immunity of ICs independently of frequency without impairing IC performance. A transverse electromagnetic (TEM) cell was used to simulate and measure loaded and unloaded versions of an IC. An indirect measurement demonstrated that the susceptibility of a commercial microcontroller (ATMEL SAM3S4B) was significantly reduced (~48% less failure rate for a loaded compared to an unloaded IC) thanks to that technique. Moreover, it was shown that the immunities to both E- and H-fields were enhanced in presence of a non-ferromagnetic dielectric material being much less expensive than commonly used ferrites. The overall results demonstrate the effectiveness of the proposed technique as a potential candidate to mitigate the radiated susceptibility of electronic devices.

I. Introduction

Electromagnetic compatibility (EMC) and electromagnetic immunity (EMI) testing are becoming major requirements to ensure proper operation of increasingly complex integrated circuits (ICs) [1], [2]. Particularly, to counteract the ever increasing clock speeds and switching currents, the reduction in voltage supply lowers the noise margin of digital circuitry and consequently IC susceptibility [3]. Therefore, EM interference can cause catastrophic failures in microcontrollers (μCs) which, incidentally, play a major role in embedded systems [4]. This has led the EMC/EMI regulatory commissions (e.g. international electrotechnical commission IEC [5]) to define procedures to assess the EM immunity of ICs.