Automated Co-Design Methodology for DC/DC Buck Power Stage and Sliding-Mode Controller to Meet Performance Specifications

The main contribution of this work is a co-design process for buck DC/DC converters, aimed at facilitating the development of a system that meets performance specifications from the earliest stages. This process incorporates a cascade control strategy—featuring a PI regulator for the output voltage and a sliding-mode controller for the inductor current—and is implemented as a software tool that guides the designer in selecting off-the-shelf components, determining feasible ranges that balance cost, size, efficiency, and electrical performance. From an engineering perspective, the tool is modeled using component and sequence diagrams, ensuring modularity, traceability, and step-by-step validation between the electrical design and control modules. The validity of this design process is demonstrated through an application that uses two USB Type-C ports. The experimental and simulation results, obtained using commercially available components, confirm that even in the worst-case scenario, the closed-loop system meets all USB-PD specifications, exhibiting precise voltage regulation, fast dynamic response, and well-damped inductor current. Consequently, this work not only proposes a systematic and practical design method but also supports it with concrete evidence of its ability to generate robust, implementation-ready solutions.