TITLE:
An Analysis of Buck Converter Efficiency in PWM/PFM Mode with Simulink
AUTHORS:
Cheng Peng, Chia Jiu Wang
KEYWORDS:
PFM; PWM; Buck Converter; Efficiency
JOURNAL NAME:
Energy and Power Engineering,
Vol.5 No.3B,
July
31,
2013
ABSTRACT: 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.