| Digital control has been a hotspot in power electronics field because of its high feasibility and high precision. This paper based on a digital controlled Phase-Shifted Full-Bridge(PSFB), to overcome the shortage of full wave rectifiers in secondary side, introduces DSP based an improved current double rectifier application. In comparison with the big gap for soft switching of two legs in PSFB used full wave rectifier circuit, the introduced circuit can realize soft switching for both legs in wide load range. In addition, the circuit can get rid of the resonant inductor lies in the full wave rectification circuit, consequently, the duty loss can be very little. More over, the rectifier diodes have nature transition, so no voltage spike caused by diode's reverse recovery. In a platform built around DSP56F8323, the system is controlled by DSP completely and the over-voltage and over-current protection are done also, moreover, the DSP can communicate with the primary side DSP which is used to control a soft-switching interleaved PFC. The communication with PC is also built to monitor the system operation The paper presents a PSFB DC/DC converter with current doubler rectifiers based on the platform of DSP MC56F8323. The platform not only finishes the whole control of the DC/DC converter but also the monitor to the system is also done in the platform. To utilize the DSP fully, MOSFET is selected as rectifier instead of diode. The Drive methods are introduced in the paper and analyse the method of synchronous signal which is generated by DSP. At the end, the operation of current doubler rectifier is verified by a 500W prototype. And the synchronous MOSFET rectifier is also done and the experiment result shows that the synchronous rectifier is feasible.
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