Digitally-controlled high-frequency DC-DC buck converter

A through and detailed design procedure and evaluation of two types of digital controllers for a dc-dc buck converter working in Continuous Conduction Mode (CCM) is described in this paper. The converter operates at a switching frequency of 500 KHz. The controller is designed on the basis of “digital redesign” and “direct digital design” approaches. The performance of the approaches is compared in terms of both the bandwidth and the phase margin of the control loop, as well as the output transient response. Matlab/Simulink simulated results validate the design.