Study Of Synchronous Rectifier Self-driving Technique In The Half-Bridge Current-Doubler Converter With Integrated Magnetics

As constantly development of information technology, The DC power supplymodule is required to have output with lower voltage, higher current, and have thecharacteristics of high efficiency, high power density and fast dynamic response,that makes designers face more challenges. For example, Studying VRM, which isthe power supply to CPU, is an important part of the low-voltage/high-currentDC/DC converters. Then, symmetrical half-bridge current-doubler circuit topologyis selected in the isolated low-voltage/high-current DC/DC converters. In order toimprove the efficiency of the converter, the synchronous rectification technologyhas been universally application. In addition, the magnetic integration technologyhas been widespread concerned, because it is benefit of improving converter’s powerdensity and the performance. Therefore, it is necessary to research the synchronousrectification technology and the magnetic integration technology for the converter.This paper introduces symmetrical half-bridge with current-doubler converterfor the study. First, improve the converter efficiency from the start, for the doublerrectifier switching dead time, making the general self-driven synchronous rectifierdrive signals can not provide, leading to the body diode conduction, therebyreducing the efficiency of synchronous rectification the problem studied A newself-driven synchronous rectifier doubler circuit, the dead time synchronizationrectifier conduction, and its working principle are introduced to analyze the impactof synchronous rectifier drive signal quality parameters, the design parameters aregiven. Then consider increasing the converter power density, select an existingmagnetic doubler rectifier integrated solution, the equivalent magnetic circuitanalysis, magnetic integration and integration of the auxiliary drive winding, andfurther improve the converter’s power density, but also through auxiliary drivewinding around a different method to improve the driving voltage waveform, giventhe design of integrated magnetics. Finally, simulation and prototype experimentsshow that the method can improve the converter’s efficiency and power density, and improve the converter’s performance, with good usability.