Intensity Estimation of Electromagnetic Emission from Individual ICs Based on Noise Source Amplitude Modulation and Correlation Analysis

Abstract

In order to reduce electromagnetic interference at low cost, we propose a method to estimate the intensity of the electromagnetic emission for each IC. In this method, the intensity is estimated based on the ratio of noise source levels obtained by the temporal change in EM emissions when the switching currents generated in potential noise sources are intentionally modulated. In this paper, we applied the proposed method to a printed circuit board with multiple ICs and estimated the intensity of electromagnetic emission originating from individual ICs. Moreover, the accuracy of the estimation was evaluated by comparison with measurements made when the IC was individually driven. The results indicated that the emission intensity can be estimated with high accuracy when all the emissions caused by each IC are in phase.