Digital current-mode controller for DC-DC converters

This paper introduces a digital average current-mode controller architecture based on a low-resolution current A/D converter and a simple digital controller realization. The proposed approach combines advantages of practical digital realization and current-mode control for DC-DC converters operating at high switching frequencies. An experimental test circuit includes an experimental prototype current A/D converter, a controller implemented on an FPGA, and a 6 V-to-1.8 V, 10 A synchronous buck power stage operating at 200 KHz. Experimental verification results are described.