An Analysis of Buck Converter Efficiency in PWM/PFM Mode with Simulink


This technical paper takes a study into efficiency comparison between PWM and PFM control modes in DC-DC buck converters. Matlab Simulink Models are built to facilitate the analysis of various effects on power loss and converting efficiency, including different load conditions, gate switching frequency, setting of voltage and current thresholds, etc. From efficiency vs. load graph, a best switching frequency is found to achieve a good efficiency throughout the wide load range. This simulation point is then compared to theoretical predictions, justifying the effectiveness of computer based simulation. Efficiencies at two different control modes are compared to verify the improvement of PFM scheme.

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C. Peng and C. Wang, "An Analysis of Buck Converter Efficiency in PWM/PFM Mode with Simulink," Energy and Power Engineering, Vol. 5 No. 3B, 2013, pp. 64-69. doi: 10.4236/epe.2013.53B013.

Conflicts of Interest

The authors declare no conflicts of interest.


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