Overload Protection in Digitally Controlled DC-DC Converters

This paper presents an approach to overload protection based on a predictive average current-mode control technique for digitally controlled DC-DC switched-mode power supplies. The proposed approach can be applied in voltage-mode or current-mode control architectures. The current limit, the converter actions upon detecting an overload, and the shape of the overload characteristic can be fully programmable. Static and dynamic operation are discussed and the results are verified on a digitally controlled 6V to 1.8 V, 10 A, 200 KHz synchronous buck prototype.

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