A CCM/DCM Dual-Mode Synchronous Rectification Controller for a High-Efficiency Flyback Converter

• Published in: IEEE transactions on power electronics Vol. 29; no. 2; pp. 768 - 774
• Main Authors: JEONGPYO PARK, ROH, Yong-Seong, MOON, Young-Jin, CHANGSIK YOO
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.02.2014; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Circuit properties; Clocks; Continuous-conduction mode (CCM); Control systems; Controllers; Converters; Convertors; discontinuous-conduction mode (DCM); Electric currents; Electric, optical and optoelectronic circuits; Electrical engineering. Electrical power engineering; Electrical machines; Electronic circuits; Electronics; Energy efficiency; Exact sciences and technology; flyback converter; Monitoring; Power supply; Rectification; Regulation and control; Resistors; Sensors; Signal convertors; Switches; Switching circuits; Switching, multiplexing, switched capacity circuits; Synchronous; synchronous rectification; Transistors; Voltage; Voltage control; Performance evaluation; Continuous mode; Rectifier effect; Continuous-conduction mode (CCM); Control system; Flyback converter; Machining; Implementation; synchronous rectification; Discontinuous mode; Current mode; High efficiency; discontinuous-conduction mode (DCM); Selector switch; Resistor; Comparative study; Monitoring
• ISSN: 0885-8993; 1941-0107
• DOI: 10.1109/TPEL.2013.2256371

A dual-mode synchronous rectification (SR) controller supporting both the continuous-conduction mode and discontinuous-conduction mode is developed to improve the power efficiency of a flyback converter. The dual-mode SR controller ensures nonoverlapped turning-on of the primary and secondary switches by monitoring the voltage level of the secondary switch. The dual-mode SR controller requiring four pins and only one external resistor has been implemented in a 0.35-μm BCDMOS process and applied to a 50-W flyback converter. The efficiency of the flyback converter is improved by upto 6.8% when the dual-mode SR controller is employed compared to the one employing the conventional SR controller.