This paper describes project work in which students must implement a pre-processing approach founded on the Σ-Δ technique, which is traditionally well suited to signal processing applications, for increasing the effective resolution of the digital pulse-width modulator in a voltage-mode controlled Buck converter. Simulations in a MATLAB/Simulink environment are first conducted in order to confirm the effectiveness of the approach. Then, experimental results obtained with a low-cost development board are presented and the educational experience is discussed.
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