The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 12, 2016
Filed:
Aug. 13, 2013
Bcd Semiconductor Manufacturing Limited, George Town, Gand Cayman, KY;
ShaoHua Fang, Shanghai, CN;
BaoZhen Chen, Ames, IA (US);
Qiang Zong, Shanghai, CN;
YaJiang Zhu, Shanghai, CN;
Other;
Abstract
A synchronous rectification circuit for a power supply includes a power switch for coupling to a secondary winding of a transformer of the power supply and an output capacitor of the power supply. The power switch includes a four-terminal MOSFET having a source, a drain, a gate, and a body. A body diode is formed by a junction between the body and the drain or by a junction between the body and the source. The body diode is coupled in parallel to the source and drain of the power transistor. A control circuit is configured to provide a control signal for controlling an on/off state of the power switch in response to a voltage condition of two terminals of the power switch. When the body diode makes a transition from reverse bias to forward bias, the control circuit causes the MOSFET to turn on, and when the forward bias voltage drops below a reference voltage, the control circuit causes the MOSFET to turn off. When the body diode makes a transition from forward bias to reverse bias, the control circuit causes the MOSFET to turn off.