This paper presents a high-efficiency isolated ac-dc converter topology. The proposed converter consists of a full-bridge diode rectifier, an isolated resonant dc-dc converter, and only one controller. The proposed converter provides the soft-switching technique for all components operating at high frequency, allowing for an improvement in power density without a cost of power-conversion efficiency. Furthermore, by using a novel control algorithm that controls both power factor and output power, the converter performs ac-dc power conversion in only a single-power-processing step. These characteristics enable the proposed converter to provide high efficiency, high power density, and a high power factor. A 2-kW prototype was implemented, and its performance and validity were evaluated based on experimental results.