Electromagnetic Conductive Immunity of a Microcontroller by Direct Power Injection

This paper deals with direct power injection (DPI) test research and its fabrication of test circuit board, construction of test system, and failure analysis. Such a sensitivity test aims to assist designers in assessing the IC’s (integrated circuits) susceptibility to radio frequency interferences (RFI) during the design phase of the IC. The IEC 62132-4 standard method of immunity measurement is applied to a microcontroller chip to evaluate the sensitivity of specific pins to direct power injection conducted interference. Through experiments, get the sensitive threshold and interference amplitude of the microcontroller. And through the optical microscope and scanning electron microscope to explore the reasons for the failure of the microcontroller, the main damage mechanism is thermal stress.

I. Introduction

Due to the high frequency, high speed and high integration of information technology, modern integrated circuits (IC) work in an increasingly complex electromagnetic environment. Continuous-wave electromagnetic interference is a kind of complex electromagnetic environment faced by contemporary electronic products. International standards that assess the compatibility of an IC have been proposed to guide IC design companies towards electromagnetic compatibility. IEC 621324 is one of the standards that assess electromagnetic conducted susceptibility of IC [1,2]. In this paper, research the effect of the direct power injection (DPI) method on a microcontroller by using the DPI injection probe. Through the experiment, find that the package of the microcontroller plays a key role in the microcontroller conducted susceptibility. At the same time, to study the mechanism of the conduction failure, the morphology of the failed or burned chip was observed under the electron microscope.