We present here a prototype of a Spread Spectrum Clock Generator designed for switching DC/DC converters, which has been optimized in accordance to EMC international regulations to improve EMI reduction with respect to standard approaches. Such an optimization has been obtained trough the theoretical computation of the power spectrum as measured by a spectrum analyzer when a chaotic or random-like PAM modulating signal is employed. To experimentally validate the achieved theoretical results, the circuit has been fabricated in CMOS 0.18 μm technology, and embeds two simple and effective modulators, the first one relying on a full analog hardware, the second one on a simple digital core. Measurements on a DC/DC converter in accordance with EMC regulations confirm that the prototype can achieve a 7 dB EMI reduction improvement with respect to classical solutions based on out of audible triangular waveforms
Short-term optimized spread spectrum clock generator for EMI reduction in switching DC/DC converters
PARESCHI, Fabio;SETTI, Gianluca;ROVATTI, Riccardo;
2014
Abstract
We present here a prototype of a Spread Spectrum Clock Generator designed for switching DC/DC converters, which has been optimized in accordance to EMC international regulations to improve EMI reduction with respect to standard approaches. Such an optimization has been obtained trough the theoretical computation of the power spectrum as measured by a spectrum analyzer when a chaotic or random-like PAM modulating signal is employed. To experimentally validate the achieved theoretical results, the circuit has been fabricated in CMOS 0.18 μm technology, and embeds two simple and effective modulators, the first one relying on a full analog hardware, the second one on a simple digital core. Measurements on a DC/DC converter in accordance with EMC regulations confirm that the prototype can achieve a 7 dB EMI reduction improvement with respect to classical solutions based on out of audible triangular waveformsI documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
