Zero-Voltage-Switch Full Bridge with Self-Driven

This invention proposes a high frequency and high efficiency topology. Compared to conventional phase-shift full bridge, the topology is the same and the only difference is the control strategy. Based on the control strategy, Zero-voltage-switch (ZVS) can be achieved. Another benefit from the control strategy is that the gate signal for synchronous rectifier can be derived from the center points of bridge legs directly and easily. Compared to the conventional self-driven, the proposed self-driven does not have severe ringing and the waveform is pretty clean. Analysis and experimental results show that the self-driven can reduce gate driver loss and body diode conduction loss significantly. A 1.2V/70A, 1MHz prototype is designed and the experimental results show that it can achieve 81.7% efficiency at full load. This invented circuit is really simple and highly efficient. It can be a very good candidate to be used in the field of low voltage, high current application such as 48V power pod for microprocessors.


Patent Information:
App Type Country Serial No. Patent No. File Date Issued Date Patent Status
US Utility *United States 10/350,330 6,819,574 1/24/2003 11/16/2004 Expired/Unpaid Fees
US Continuation-in-Part *United States 10/852,683 7,016,203 5/25/2004 3/21/2006 Issued
For Information, Contact:
Li Chen
Licensing Associate
Virginia Tech Intellectual Properties, Inc.
(540) 443-9217
Ming Xu
Fred Lee
Yuancheng (frank) Ren