Evaluation of the Electromagnetic Emission of ICs Using Different Spread Spectrum Approaches

This paper examines the use of spread spectrum clocking approaches to reduce the increasing electromagnetic emissions caused by the constantly rising switching frequencies of modern electronic systems. The approach to reducing these emissions is based on spreading the spectral power of a narrowband signal over a certain bandwidth in order to reduce the peak amplitude. We will compare the performance of a spread spectrum clock generator based on the random method with one using simple frequency modulation with a triangular modulation signal and relate it to their theoretical behavior. Furthermore, we will perform CISPR-compliant emission measurements with different detectors of an EMI receiver and compare the influence on the measurement results.