Search Results - julu+sun

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Interleaved Inductor-Less Resonant Converters with Auto Transformer
CPES proposed inductor-less resonant converter has high efficiency. However, the output voltage ripple is huge since it uses the leakage inductor resonating with output capacitor. This invention solved the ripple problem by interleaving two-phase and use autotransformer to do the voltage averaging. The simulation result demonstrates that the ripple...
Published: 9/11/2012   |   Inventor(s): Ming Xu, Julu Sun, Fred Lee
Keywords(s): Electronics
Category(s): Electrical
Novel Non-Isolated Bus Converters
With switching capacitor technology, a family of non-isolated bus converter without output voltage regulation can greatly increase efficiency, especially at light load. Without the magnetic component or with tiny inductor, the proposed bus converters can realize about 10X power density than the conventional approach. With these compelling traits,...
Published: 9/3/2012   |   Inventor(s): Ming Xu, Julu Sun, Fred Lee
Category(s): Electrical
Using JFET as Synchronous Rectifier to Achieve High Efficiency at High Frequency for Future VRM
This invention disclosure proposed a JFET based buck converter with the targets to eliminate body diode conduction loss and to reduce gate driver loss of synchronous rectifier. A self-driven scheme is used to ensure there is no dead time between the top switch and the bottom JFET in the circuit, and gate driver loss is greatly reduced by connecting...
Published: 9/3/2012   |   Inventor(s): Ming Xu, Julu Sun, Jinghai Zhou, Fred Lee
Keywords(s): Electronics
Category(s): Electrical
Non-isolated Inductor-less Soft-Switching Bus Converter with Self-Driven
This invention proposes a simple topology for the first stage of non-isolated two-stage applications. The output inductor is eliminated. The magnetizing current is used to achieve ZVS for all switches. By choosing leakage inductance and output capacitance carefully, the turn-off current for the primary switch is very small and ZCS is achieved. Most...
Published: 9/3/2012   |   Inventor(s): Yuancheng (frank) Ren, Julu Sun, Ming Xu, Fred Lee
Keywords(s): Power Conversion/Control
Category(s): Electrical